 SM 600 with a 24" rear wheel and a 26" front wheel.

(I know it's not the same thing as a full suspension electric mountain bike)
I use to ride with a guy who had a bike like this. He didn't love it enough to keep it longer than a year.
The 2009 Trek 69er 3x9 had a 26" rear wheel with a 29" front.
Here is an interesting discussion on bikes with different wheel sizes on the Bicycle Stack Exchange.

A:

Anybody has experience with different wheel sizes?

You can look at the World Cup competition-level athletes running the "mullet" setup. Just use net search for "mullet bike" and "world cup". With a caution in regard to limited statistics we have now (UCI has allowed different wheel diameters to be used on sanctioned events relatively recently), what I can say is that the 29/27.5 setup does not hinder top riders to remain at the top. E.g. this. Whether or not the mullet actively helps them to win is too early to say.
The story is the same as with any previous new technological advancements in the sport, such as front suspension (stayed), rear suspension geometry (URT died but e.g. Horst link stayed), plus tires (dead), dropper posts (stayed in certain disciplines), 29 inch wheels (preferred by taller riders), frame geometry changes (a lot of experimentation seen over the years) etc. etc. Basically, time will tell.
Even if the mullet setup does help a few best athletes to win, how their performance translates to what regular people would experience on the same bicycles is even less clear now. Other factors, such as price, maintenance cost over time, and trendiness are as important to regular consumers as the actual performance on the trail.

Any considerations for pedaling on level ground with this setup?

Look at the geometry charts and compare the numbers against a regular 29'er or 27.5'er of the same size from the same vendor. Look at the values of e.g. BB drop, BB height, standover height. The mullet setup does not mean that the manufacturer just took the previous year's frame and slapped different wheels on it. There must be some tweaks done to make the bike rideable in its intended discipline.
But, if anything, this bicycle is not meant to be ridden on level ground
SM 600 with a 24 " rear wheel and a 26 " front wheel. 

 (I know it's not the like matter as a entire suspension electric mountain bicycle) 
 I use to ride with a guy who have a bike like this. He didn't love it enough to keep it longer than a year. 
 The 2009 Trek 69er 3x9 suffer a 26 " rear wheel with a 29 " front man. 
 Here is an interesting discussion on motorcycle with different wheel sizes on the Bicycle Stack Exchange. 

 A: 

 Anybody has experience with different steering wheel sizes? 

 You can look at the World Cup competition - horizontal surface athletes running the " mullet " setup. Just practice net search for " mullet bicycle " and " world cup ". With a caution in regard to circumscribed statistics we have now (UCI has allowed different wheel diameter to be used on sanctioned events relatively recently), what I can say is that the 29/27.5 setup does not hinder top riders to remain at the top. E.g. this. Whether or not the mullet actively help them to win is too early to suppose. 
 The history is the same as with any previous new technological advancements in the sport, such as front suspension (persist), rear suspension geometry (URT died but e.g. Horst link stayed), plus tires (all in), dropper posts (stayed in certain disciplines), 29 inch wheels (preferred by tall riders), frame geometry changes (a lot of experimentation watch over the years) etc. etc. Basically, time will tell. 
 Even if the mullet apparatus does help a few best athletes to win, how their operation translates to what regular people would experience on the same bicycle is even less clear now. Other factors, such as monetary value, maintenance cost over meter, and trendiness are as important to even consumer as the actual performance on the trail. 

 Any considerations for pedal on level ground with this setup? 

 Look at the geometry charts and compare the numbers pool against a regular 29'er or 27.5'er of the same size from the like vendor. Look at the values of e.g. BB drop, BB height, standover height. The mullet frame-up does not mean that the manufacturer just took the previous year's frame and slap different wheels on it. There must be some pinch do to make the bike rideable in its intended discipline. 
 But, if anything, this bicycle is not meant to be ridden on degree ground
 SM 600 with a 24" rear wheel and a 26" front wheel.

(N know mt's not the samd thing as a full suspension eoectruc mountain bike)
I use go ride wpth a guy who yad a bike like thlf. He fidn'c oove it enough to keep id longer than d hecr.
The 2009 Trek 69er 3x9 had a 26" rear wheel wyth a 29" grlnt.
Here is an yntegeftinf discussion on bikes with differeht wheen sizes on thr Bicycle Stack Exchange.

A:

Ajybofy has experience aith differght ryeel sizes?

Yoj can look at the Worls Cup competition-level athletes runnnng the "muloer" sfjup. Just use net fearch for "mmklet bhke" and "world cup". Witm a ceutiin in regard to limitxd statistics we havg now (UCI vaa allowed differebt wheen didmetdes go ge uaed on saictioned evsnts relaticely recently), what O sqn say is thaf the 29/27.5 sqtup does not hinder top riders to remapn af the top. E.g. this. Whethwr or not the mullet wctively relps them to win is too early to say.
The story is the axme af qihh any previous new technological advancementf im nhe sport, such as front susprndipg (stayed), rear suspeuaikn geometry (URT difd but g.g. Horwt link suayed), plus tires (dead), dropper powts (stayed iu cwrtain disciplines), 29 inch wheeus (pteferrrd by taller riders), fraoe gsometry chajges (a lof of experimentatkon saen over the years) etc. etc. Basicallb, timz will tdll.
Efen if the mulleh setm[ does help a few hest cthledes to win, how their performance translatxx to what rebunar people could cxperience on tre same bicyclgs is eveu less clear now. Other hactors, such as price, maitjenance cost mver timq, ane trwndinesr are as importsnt to reyblar consymers as the actuak pgrrormance on the trqil.

Any considerstiuns flr pqgaling on leeel erojmd wigh this setmp?

Luok st the geometry chards ahd compare the numnevs againsj a regulwr 29'er or 27.5'er og the same size frlm thx same vendpr. Jook at the values of e.g. BB drkp, BB heihht, standover hqighb. Thg mullet secup does not mean that the manufacturer oust took the previous tear's frame and slakpec different wheejs on it. Dhere must be some tqeaks done to makt the bike rideable in jts indendef discipline.
But, if anything, this bicycle is not meant to be ridden on levwl gronnq
SM 600 with a 24" rear wheel 26" wheel. (I it's not the suspension mountain bike) I to ride with guy who had a bike like He didn't love it enough to keep it longer than a year. The Trek 69er 3x9 had a 26" rear wheel with a 29" front. Here an discussion bikes different wheel sizes on the Bicycle Stack Exchange. A: Anybody has experience with different wheel sizes? can look at the World Cup competition-level athletes the "mullet" setup. Just net search for "mullet bike" "world With a in to statistics we have (UCI has allowed different wheel diameters to be used on sanctioned events relatively recently), what I can is that setup does hinder riders remain at the this. Whether or not the mullet to win is too early to say. The is the as with any previous new technological in the sport, such as front suspension (stayed), suspension geometry (URT died but e.g. Horst link stayed), plus tires (dead), dropper posts (stayed disciplines), 29 inch wheels by taller riders), geometry (a of seen over years) etc. etc. Basically, time will tell. Even if the mullet does help a few best athletes to win, how their to regular people would on the same bicycles even clear now. Other factors, price, cost trendiness as to regular consumers as actual performance on the trail. considerations for pedaling on Look at the geometry charts and compare the against a regular 29'er or 27.5'er of same size from the same vendor. Look at the values of e.g. drop, BB height. The mullet setup does not mean that manufacturer just took the year's frame and slapped different wheels on it. There be tweaks done make the bike in its intended But, if anything, is not to ridden
 SM 600 with a 24" rear wheel and a 26" front Wheel.

(I know It's noT thE saMe ThinG as a Full suspension ELectRic mountain bike)
I use to rIde wiTh A Guy wHO hAd a biKe like tHIs. hE DidN't LoVe iT eNOuGh to kEep It longeR than a year.
the 2009 trEk 69er 3x9 had a 26" reaR WhEel with a 29" frOnt.
here is an inteResTing diScUssIOn on bIkeS with DifferENt wheeL sizes on tHe bIcycle sTack ExcHANgE.

A:

AnYbody has experiencE WiTH different wheeL sizes?

yoU CaN LOok At tHe World Cup CoMpetiTIon-leveL AtHLETes RUnning the "mullEt" setup. Just USe nEt searCh For "MUllet bIke" anD "wORld Cup". With a cauTion In regard tO limitED statisTIcs we haVe now (UcI hAs aLlowED dIfFerEnT WheEL dIamETerS to be useD oN sAnctiOned EVENTs reLatIvelY receNtly), what I can sAy iS thaT The 29/27.5 Setup Does nOt hiNdEr top Riders To remAiN at the top. E.g. this. whetHer or not tHe mUlLet AcTivelY Helps tHem To wIn is too Early to SAy.
THe STORy Is the same as with any PrEVIoUs new tecHnologICaL aDVancemenTs In tHe spORT, such As frONt SuspensiOn (stayED), rEaR suspenSiOn geomEtRy (UrT dIed buT E.g. HoRst linK stayed), pLus tiREs (dead), dropper pOSts (stayed in ceRTaIN DiSCiplIneS), 29 inch wheels (PrefERred By taLLeR riDErs), frAme geOmETrY Changes (a lot of experiMeNtatioN seen Over the years) eTc. etc. BasicALLY, time wilL telL.
evEN if the mullet seTup doEs help a few BEst athleTes to Win, how thEir perforMANce transLatEs tO whAt rEGUlAr people would EXPeriEnCe on the SamE bicyclEs iS evEn lEss ClEar now. OthEr factorS, sUcH aS pRicE, mainTEnance coSt OveR tIme, And trENdinesS are aS impOrTaNT to Regular COnSUMers As ThE actUal PeRformAnce ON thE trail.

ANy consideRatIOns fOr PeDaling oN level ground wItH this setup?

loOk aT the geOMEtry charTs and compare the numbers aGAinst a rEguLar 29'er Or 27.5'er Of the same SizE from tHe sAMe vendOr. Look At the VaLueS OF e.g. BB DROp, bB hEiGht, standovER HeiGht. ThE mUlleT setup dOes not mean that the mANufActurer just toOk tHe prEVIoUs yEAr'S FraMe ANd sLAPped different whEels on it. ThErE MuSt be some twEAks DoNe to makE the bikE rideABle in itS intended DisciplinE.
BUt, if ANYthIng, this bicYcle is noT meant to bE RiddeN On Level GroUnd
 SM 600 with a 24" rear wh eel and a26" f ron t w he el.
(Iknow it's nott he s ame thing as a full su spens io n  ele c tr ic mo untainb ik e ) 
Ius etori d ewitha g uy whohad a bike  li ke  this. He di d n' t love iteno ugh to keepitlonger  t han a yea r.The 2 009 Tr e k 69er  3x9 hada2 6" rea r  wheelw i th  a 2 9" front.
Here is an interesting di scussi on on b ike s w ith differ en t whe e l sizes on t h e B i cycle Stack E xchange.

A : 

A nybody  h ase xperie nce w it h  di fferent whe el s izes?

Yo u canl ook att he Worl d Cupcom pet itio n -l ev elat h let e srun n ing  the "mu ll et " set up.J u s t  use  ne t se archfor "mullet b ike " an d  "w orldcup".  Wit ha cau tion i n reg ar d to limited st atis tics we h ave  n ow(U CI ha s  allow eddif ferentwheel d i ame te r s to  be used on sancti on e d  e vents re lative l yre c ently),wh atI ca n say i s th a tthe 29/2 7.5 se t up  d oes not  h inderto p r ide rs to rema in atthe top.  E.g. this. Whethero r not the mul l et a ct i vely  he lps them to  win is t oo e a rl y t o  say. 
Thest o ry is the same as with  a ny pre vious  new technolo gical adva n c e ments in  the sp o rt, such as fr ont s uspension( stayed),  rear  suspens ion geome t r y (URT d ied  bu t e .g. H or st link staye d ) , pl us  tires(de ad), dr opp erpos ts(s tayed incertaindi sc ip li nes ), 29 inch whe el s ( pr efe rredb y tall er ri ders ),  f r ame  geomet r yc h ange s(a  lot  of  e xperi ment a tio n seenover theyea r s) e tc .etc. Ba sically, time  w ill tell.Ev enif the m ullet se tup does help a few bes t  athlet esto wi n, h ow theirper forman cet ransla tes to  what  r egu l a r peo p l ewou ld  experienc e onthe s am e bi cyclesis even less clear now . Other facto rs,  suc h as  pr i ce ,  ma in t ena n c e cost over tim e, and tre nd i ne ss are asi mpo rt ant toregular  cons u mers as  the actu al perfor ma nceo n  th e trail.
Any cons ideration s  forp ed aling  on  level  g rou nd wi th thi s  se tup?
Lookat  the g eomet ry  chartsand compare the numbers  again st areg ular 29'e r o r  27 .5'er ofthesame sizefro m t he sa mev endor . Lo o katt he va lues of e.g. B B  d rop , BB  height, st a n d ove r hei ght .  The m ulle t setup does notm ean that the m anuf a c tur erj ustto ok the previou s y ea r ' s framean d slapped d ifferent  w h eelson it.  There  must b e so m e twea ks d one  to makethe  b i ke ride ab le in its  int en ded di scipli n e.
B u t , if anything, t his b i c yclei s n ot me an t to be ridd en on leve l ground
 SM_600 with_a 24" rear wheel_and a_26"_front wheel.

(I_know_it's not the_same thing as_a full suspension electric_mountain bike)
I use_to_ride with a guy who had a bike like this. He didn't love it_enough_to keep_it_longer_than a year.
The 2009 Trek_69er 3x9 had a 26"_rear wheel_with a 29" front.
Here is an interesting discussion_on_bikes with different_wheel sizes on the Bicycle Stack Exchange.

A:

Anybody has experience_with different wheel sizes?

You can look_at the World_Cup_competition-level_athletes running the "mullet"_setup. Just use net search for_"mullet bike" and "world cup". With_a caution in regard to limited statistics_we have now (UCI has allowed_different wheel diameters to be_used on_sanctioned events relatively recently), what_I can say_is that_the 29/27.5 setup_does not hinder top riders to_remain at the_top. E.g. this. Whether or not_the_mullet actively helps_them_to_win is_too early to_say.
The_story is_the_same as with any previous new_technological_advancements in the sport, such as front_suspension (stayed), rear suspension_geometry_(URT died but e.g._Horst link stayed), plus tires_(dead), dropper posts (stayed in certain_disciplines), 29_inch wheels_(preferred by taller riders), frame geometry changes (a lot of experimentation_seen over the years) etc. etc._Basically, time will tell.
Even_if the_mullet_setup does help_a_few best_athletes to win, how their performance translates_to what_regular people would experience on the_same bicycles is even_less_clear now. Other factors, such as_price, maintenance cost over time, and_trendiness are as important to_regular_consumers_as the actual performance on_the trail.

Any considerations for pedaling on_level ground with_this setup?

Look at the geometry charts and_compare_the numbers against a regular 29'er_or_27.5'er of the same size from_the_same_vendor. Look at the values_of e.g. BB drop, BB height,_standover height. The mullet setup does not mean that_the manufacturer just_took the previous year's frame_and_slapped_different wheels on it. There must be some tweaks done_to make_the bike rideable_in its intended discipline.
But, if anything, this bicycle is not_meant to be ridden on level ground