I liked CBR but I liked GSXR better. Did not test ride a 636 and not a big fan of R6(too small for me 6'4 205lbs and ride not as good as my gixxer). As somebody else said, go to a dealership sit on your choice of bikes, select 2,3 models you feel comfortable on and then go to Craigslist (or anyother web portals) and test drive few and select THE ONE