Best way to answer your questions is to go down the track and have a chat with the guys there. OK everyone (nearly) seems to be running B4's, so if you get one of them there will always be somebody there with a part if you need it.

But since most of the time you dont need any, that shouldnt be a problem.

Another question is what sort of $$ are you looking at spending?

2WD buggy is the go at the moment but with the release of quite a few excellent 4WD buggies out now, this may prove to be the next hottest thing...