Agreed with what has been said so far. With your mild cam, your 600 should work fine. Of course, that might depend on what "mild" is in your case.
I ran both a 625 and 500 (both Carter versions) and for my totally stock engine the 500 was a bit snappier, like has been said. However, the 625 did work very well too, so it sounds like either one should be fine for your mildly built 302.
And once you get used to it, I think you'll really like the ease of tuning/tweaking of the AFB design.
Paul