Originally Posted by HillRider
I have no idea why SRAM derailleurs should work better and need less maintenance than Shimanos. My experience is Shimano derailleurs work extremely well and last for huge numbers of miles on little maintenance.
Shimano rear derailleurs are very fine, provided (1) the cable isn't too long and (2) the derailleur cable is routed along the seat stay. If the cable is too long or if the cable is forced to make that 180 degree bend before entering the derailleur, they may work rather less well. If the cable is too long AND is bent 180 degrees, then they certainly become troublesome. This is the case on my recumbent, and there isn't much I can do about it.
SRAM ESP derailleurs have (1) a smaller actuation ratio, meaning the shifter pulls more cable than Shimano, so there's less tension in the cable (less friction) and it's less affected by bad housing ends and housing bends, and (2) a much more sane cable entry. The flip side of SRAM derailleurs if that I find them more cheap-looking than Shimano ones, and SRAM has a very substandard shifter offering.
So that's why I want to keep my Shimano shifter, convert the 2:1 ratio to 1:1 right after the cable exits the shifter, then run the "SRAM-ized" cable to a SRAM derailleur and enjoy crisper shifts and not having to goof with the adjustment and not having to service the cable quite so often.