Hey Jack 8P
As far as I know, the difference between the 3.2 and 3.2r isn't much. The 3.2r comes with all red anodized aluminum stuff, the 3.2 is silver. Same parts tho. Someone correct me if I'm wrong, but I'm pretty sure the 3.2 has a thinner chassis too. The Gen-X is a completely different car. New chassis, rear pod, front end. You can, however put the gen-x front end on the 3.2 and it works real nice on carpet. Thats what I did with my car.
The 3.2 is a great car, it will certainly be competitive if set up correctly.