i would get a kfx400 if i where you. im sure you can handle a 700, but stillv1 is right. they are heavy and do need getting used to. but with your size i think you would like the 400 better,

 

i got a 700 and a brute force and the 700 just sits. its got stage 2 jets and dual exh and my friends worked honda 450 smokes me. it is a heavy pig but a fun pig. sure you could ride it but wouldnt be as fun as some of the other bikes mentioned

 

dude just ride one, screw the throttle crap, i got a banshee when i was 14 and only 140 i loved the speed of it and 2 months later i piped it and filtered and now i want to buy a 421 cub lol, i went from a trailblazer to a banshee with no problems i think you will live