And with a good camera a tripod is even more mandatory

so I hope you can put aside the 20 extra dollars needed
No seriously, I know I always keep hassling ppl for blurry pics and such, but I just think it is a pity to see a rare car and come back with just "bad" pics.. it's so nice to look back at rare cars you saw months or years earlier and to do so, good pics help a bit
Don't think a good camera solve every problem

A good camera basically shows your "problems" even more

because when you take a bad pic with an average/crappy camera, ppl can still think it is mostly up to the camera, while, when I see a crappy pic taken with a 300 or 350D, I want to cry
BTW, do you plan to buy also an extra lense? Or not? If not I am looking forward to read if the standard one can be enough (but I seriously doubt).