Man i have to say you already have a nice bike. I dont know how long you have been riding, but i have owned four 600's over the course of eight years and have ridden just about everything out there at one time or another. The liter bikes are amazing if you like to be able to pull the wheel at 80 or 90 mph going down the highway or just like the higher speed stuff, but if you are like me....I live in tennessee and we have a lot of curves here. A 600 will always feel more comfortable in the corners, switchbacks etc. so really its all up to you and the way you want to ride. Theres not much i cant do with a 600, but i have decided recently i want both... So now i'm shopping for my 1k. Good luck whatever you decide. Just my 2 cents.

 

ok here we go,
i rode a 2003 600rr for the last 2 years first crotch rocket i ever rode because i would not ask to ride anyone elses just bought one. when the 1000rr came out i loved it but i knew i wasent ready for it so i got the 2 years on the 600 and now i own a 2006 blue yellow 1000rr. now the r6 and the 600rr are not much different only that yamaha over stated the rpm range of the new r6. now you no when you twist the throttle on the r6 you waht until about 8000 to really hang on well the 1000rr you dont wait. the other big difference doing wheelies if you like doing them the 600 rr i had done a lot of mods to and it was really something but snapping the throttle on the 600rr you no how the front wheel just jumps up at you and just scares the crap out of you i never could get use to that and never could do what i thought was a discent wheelie i would be to low to high or in between . now keep in mind iam 53 yearrs young i rode the 1000 for a 1000 feet the other night just playing with the throttle on the back wheel. you just give it throttle and it comes up give a little more it comes up a little more a little more throttle a like magic it is at the balance point and i hvae never experenced that until the other night felt great. and when riding the 600 bikes a 100 comes in the higher rpm range not the 1000 just twist change gears and man 100 is nothing. but like all said get use too her first because you will experance power like you never have. now the 2006 is only 20 pounds heavier then the 600rr but man they hide that weight very well i cannot ever tell the 20 pounds is their i will have to say after riding the 2003 600rr for 2 years and after all the upgrades made to the 2006 1000rr it does handle out brake and anything else you throw at it better then thre 600 did. now that is just my opinion but i have owned both. it just gives you the feeling that when you do something that the bike is going to be with you and not doing something stupid that is unexpected just keep in mind again you will experence more power then you have ever known ride safe and be careful.