Fazer 1000 nitron or hyperpro whatever rear shock ??

[celticbiker]

TBH a lot depends on how and where you ride.
If you ride in the dry on good roads once a month well within the speed limit, no lean angle and late acceleration then you probably won't notice much of a difference from the r6 mod.
On the other hand if you ride every day In varied weather and road conditions, like to make progress, accelerate before the apex and want to be able to control a rear end slide then the difference will be night and day.
I find that a lot of people ride the same with a decent shock as they did with the oem and say there's no difference, you only really notice it when you up your game.