Is there much change in finicky-ness of rear derailers moving from 8 to 9 to 10 spd? My 9 spd 105 RD seems really demanding, needs a lot of tweaking, like just w/ tire pressure changes, while my 8 spd stx RD seems bombproof, no tweaking needed when changing cassettes or rims (or both). That could be a frame thing I guess, how easy it is to properly seat the wheel.