I say get what you like.

The Rustler ain't a bad car. Can be made better with aftermarket parts. Yeah, the owner cheaped-out using a nail so his maintenance ethic may be suspect.

Two-wheel drive will certainly make you a better driver. Teaches you throttle control. All top-level racing is 2wd. It's because it's harder to drive a rwd car fast than it is to drive a 4wd car/truck. You can be pretty ham-fisted with a 4wd and still pull it thru the turn. Do the same thing with the 2wd and you'll spin it out every time if you drive it like the 4wd. That said, I'll tell you this: My buddy and I learned on Evaders (essentially Rustlers) and got pretty good at driving them fast around our track. But inevitably one of us would make a mistake and spin out. Getting back into the race takes patience to get back up to speed cuz you just can't hammer the throttle, you'll spin again. So by the time I was up to speed again, he was a half a lap ahead of me. Since we got 4wd cars, our lap-after-lap of door-to-door racing has never been better, because they don't spin out as easily, and if you do screw up enough to spin out, your recovery time is almost immediate, and you're back in the game. Made it much more fun for us.