I got a cyst over my thumb joint from Shimano rear thumb shifters, followed by a SRAM thumb shifter. About 8 cm diameter x 1 cm thick. I converted to first sun twist shifter, then SRAM twist shifter. The cable broke on the sun twist shifter after a year. The SRAM twist shifter is 2 1/2 years old and the cable is fine. The cyst went away after about a year of twist shifting. I left the front shifter thumb powered. I don't shift the front often enough to damage my thumb joint.
The pivots wore out on my SRAM front derailleur in 3 1/2 years (~7000 miles). Would only shift only 2 of 3 sprockets however it was adjusted, with worn pivot holes. SRAM was not in stock anywhere so I replaced it with a Shimano front shifter. 1/2 year it is still okay. Note Shimano has 2 or 3 levels of product. The cheapest are designed to be big sellers, are made in ***** and have materials compromises. The 2nd or 3rd tier are made in ****** out of better materials. 2nd & 3rd tier last longer. The cheapest Shimano parts are for bikes that are ridden a dozen hours in their lives before they are parked in the rain to rust up. Go through the modernbike or universalcycle websites to spot the prices of various shimano & SRAM parts. Campanile is for fanatics; I've never owned one and never will.