The most available models have rebound damping adjustment, spring preload and separate ride height adjustment (+/-5mm). If you buy from the UK YSS Research and Development Center, Firefox Racing, they will fit the shock with a spring rate of your choice for an additional charge. I think it's like 40 bucks or so.
I find their spring choice a little on the firm side (which I prefer), I am about 180 lbs without gear. I have never felt the need to change it when ordering after my first one (VF1000F).
Hawk GT
1995 VFR750F
ST1100
I think I'm on my 5th or 6th. I am very pleased with them.