I've used them (and Racetech) on most of my bikes in past 10-yrs. High-quality materials great support. Best feature is you can order them to any specs you want.
When I started racing Ninja 250 15-yrs ago, I weighed 111kg, about twice average Japanese that suspension was designed for. So simple with couple clicks to get springs that works and not bottom-out halfway through braking effort. Also got them for my commuter Ninja 250, CBR600RR track bike, VFR750, CBR600RR street bike, R1M.
Every 2-yrs or so, I overhual forks with new oil & seals. I'll get new springs calibrated for my weight. I'm down to 70kg now, so it's time for another set of springs.
That's because I take all my bikes to their absolute limits. On track and off-roading! It you never catch air and bottom out your forks, you may not notice any difference.
