I, well the dealer, put Ohlins fork springs and heavier oil in my forks and it was an improvment. The Ohlins fully adjustable rear shock replacement was a big improvement.
I've noticed on the box it says FZ1/FZ8, so looks to be the same dimensions & fitting. On the FZ1 board there is an upgrade to R6 shock thread, so you could get hold of a 2nd hand R6 shock of the correct model, or even buy the FZ1 shock off anyone wo has done the R6 mod and has an FZ1 shock lying around.