in may of 08 i got a ninja 250. and 2 months later after my 15th bday i got my motorcycle license (i live in texas). and that was plenty power for a beginner. like you i have ridden dirtbikes and four wheelers since i could ride a bicycle. the only thing similar to dirtbikes and streetbikes is the clutch work. riding on the streets is a whole 'nother monster. i put a jet kit and a two bros muffler on my 250 and it was just right (and im 6'3 206 lbs). about a month before my 16th birthday my dad surprised me with an 09 zx6r. its awesome, but im almost positive that if i hadnt of had a years worth of riding experience i would have dumped my zx6r already. the 600 to the 250 is like a corvette to a honda civic. that thing is a rocket ship. and im still not as comfortable on my zx6r as i was on my little 250. start out with a small bike, for your safety. and itll be easier on your wallet as well.
take the msf course!
take the msf course!