My newest bike (2015 Performer low racer) came equipped with Deore 10-speed trigger shifters and an XT rear derailleur. My four other recumbents are equipped with SRAM "exact actuation" shifters and derailleurs. Once I adjust the derailleurs to their "sweet spot", they hold their settings and shift perfectly. Can't say the same for the Shimano products installed on my low racer. Finally got fed up with their poor performance and ordered SRAM XO trigger shifters and a SRAM GX, mid-cage, Type 2.1 derailleur from my favorite components store (Ebay). The 2x10 GX is new design derailleur, intended for MTBs equipped with 2 chain rings. In addition to a cage lock-out feature, it has a roller bearing clutch to help control chain bounce. Further, it puts twice the tension into the return portion of the chain than my other SRAM derailleurs do (6 lbs vs. 3 lbs.). Beneficial for the low racer, because the return portion of the chain has a longer span between the derailleur's idler wheel and the front idler than do the chains on my other recumbents. The GX is 50 grams heavier than the XT, but the XO /GX combo is 90 grams lighter than the Deore/XT combo (My name is Jay, and I'm a weight weenie.  ).
 
Put 49 miles on the Performer on yesterday's Clown ride with the new SRAM components installed. Shifts were clunkier than those provided by a SRAM Rival derailleur, but fast and precise. Shifted just fine under load, pedaling up steep hills. Drivetrain vibrations I've noticed in the past (chain bounce?) were not present.