[Sanctuary]

Go the 650. It's more forgiving. ESPECIALLY for a first bike. Later, if you want to do canyon carving/racing/track then go the ZX6R - but get instruction. Heck get instruction either way. You'll start to appreciate the bike underneath you can out-ride you no matter what it is.

 

[Sanctuary]

I've seen guys (at the track) on a zx6r be passed by a chap on a 650. Either bike can be fast, it takes a good rider to learn how to ride it properly. Heck we have a twins race series (SV650, Kwaka 650) down here in NZ and the riders that come out of that series are seriously quick on anything.