Had my forks fitted with 25mm superbike cartridge but not new springs as i am 12.5 stone, also had the rear shock revalved again spring weight was fine for me, i would recommend K-Tech, been to Kais before and my recommendation is K-Tech.
You won't notice much difference with the S/B kit unless you ride it hard, maybe springs and new oil and correct air gaps, more than likely springs and a service will be all that you need, plus obviously setting up properly re damping etc.:biggrin