"Perfect for high use without pain"3.5 starson by wonkylegs
Pros: supports wrist and uses your strongest joint to click (thumb)
doesn't have lots of bells and whistles but has everything necessary for a high end CAD user
Cons: takes some getting used to
you must get the right size
Summary: I have arthritis all over but in particular my hands, wrists and elbows and I am also a CAD user two things that aren't really compatible thanks to the huge amount of mouse clicking involved. However after over 10 years of using this and its trackball predecessor I can happily recommend this. It takes some getting used to but once you've had it a while it becomes second nature. With a regular mouse I get serious pain after an hour but this isn't a problem with this mouse.
Its doesn't have loads of extras and isn't actually that sophisticated as mice go but it does all i need it to do so I can't complain.