i'm sure by now you know the sonic 3 splitup thing which i din't like. but maby this isn't too bad. i see some benifets in the sonic 3 & knuckles split. #1, sonic and knckles has a blue sphere mini game buildt in. #2, if sonic 3 and knuckles were 1 game, they may have used the sonic 3 theme and knuckles theme insted of the sonic and kuckles theme and knuckles theme which are way better, but it's not that big of deal. #3, you can play as knuckles in sonic 2 wich is enjoyable. #4, you for the first time ever see super tails if you connect sonic 3 to it. the only bad thing i can say really is if you have sonic 3 & kuckles connected to a game genie, it as tall as a building. and i can't imagine how tall it would be if you have a 32x on your genesis with sonic 3 and knuckles and a game genie in the slot. sonic and knuckles also for some reason has no save slots if sonic 3 isn't hooked up. but other than that, it's a great game. do not hesitate to buy it