Bigred is talking sense for a change since I agree with everything he's said.. Is that you carl or has someone nicked your ID ?
Just kidding!! hehe
Seriously tho, come down tomorrow evening since a few of us will be down for some informal racing and practice - weather permitting.
2WD is better if you are just starting racing I think too, not just because of the money side of things, but if you want a 4wd thats cool. The BX is a full on race car though and does need looking after more than some others, a couple of lads have them and they are great cars. The BJ4 which im just reviewing at the moment is similar but with a mostly sealed drivetrain and hence lower maintenance and with probably better parts support at the moment.
I personally think 4wd is harder to drive fast.
Like carl says, a V2 based motor would be ideal, or if you want to stump up the cash a brushless system would also be good.. Whatever you get, dont go too fast. Its a different thing to race around a track with other cars and speed doesn't matter as much as consistency.