I don't think it matters what color a QB is in the NFL anymore, they are going to be scrutinized, it's the nature of playing the most difficult and important position in all of sports.
Tebow and Vick are not comparable IMO, nor Cam. Both Vick and Cam can make every NFL throw and have super fast releases. Tebow is very unique.
For the record, I like Tebow and it's a great story, but no chance I would trade Kevin Kolb (as a Cardinal fan) for him. Of comparable age QB's, I would take Cam (in a heartbeat), Dalton, Locker, Bradford, and even Ponder (barely) over Tebow. I would take Tebow over Gabbard or McCoy, but that's it.