I almost ended up with a 05 636 until I rode my buddies. I personally felt like my 05 R6 was a better balanced (power to weight) bike. For me The 636 didn't respond well in the curves either. I'm no expert but that was my impression. Personally I don't know how much of a difference the 36cc make for everyday riding. As far as a gisxr 750 if comfort is your primary concern you may love it. They are super comfortable but I can't deal with the cyclops headlight.

 

The best looking bike of all three is the R6 hands down. Why dont you get a 06+ and slap som sprockets on that bitch to have her lift more easily

 

05 + is fuel injected and has "upside down" forks.

I had an 05, my buddy had an 05 636. I liked the R6 much better for pretty much everything. The 05 was tons more fun than the 07, it just had MORE personality and was playful.

Rode an 08 GSXR6 and thought it was awesome. No better or worse than my 05 I reckon. Never rode the CBR, but a guy I know now had an 05 CBR6 (never knew him when he had it) and he loved it.

Basically....buy any 05+ bike and enjoy.

 

You can't go wrong with any of the bikes you listed. Just try to ride each one and decide for yourself. The 750 will definitely be the quickest.

 

I find the 636's get beat on more than the others. The gsxr is the most comfortable. Is this for street or track? Track bike I would get the R6 or CBR-RR. Street I would get the GSXR 750. Both street/track would get the R6 or cbr. Unless you are looking brand new, then the 750 is about the same weight as the 600's.

 

Don't be a bitch, get a busa.

 

Ive been happy with my 636, its better than my 1st gen R6 was, but not as good as my 08 R6 was