I bought my set a few years ago contempalting doing Dovetail joints.  I just pulled it out to use with my PorterCable 1501 router.  It would not fit my base plate.  Fortunately I found my old porter-cable router that has a base fixed in one place excepted the guides. I tried the 3/8" guide and found it to be  off-center or out of round. It would not fit in the router base.  Probably had it to long to get it exchanged. I've bought a lot of other Freud products and have been pleased, but this one surprized me.