Nickwrote a review of Shimano XT RD-M8000 Rear Derailleur on May 17, 2018
Familiarity: I've put it through the wringer
I've ridden the XTR 11spd groupset, and decided that at half the cost, using the same design with heavier materials, it would be worth trying the XT derailleur and cassette (XTR shifter). Boy was I happy! It was nearly impossible to tell the difference in the XTR full groupset I rode vs my XT with XTR shifter. Shifts like butter, no stutter or interrupt mid spin, no hard clunks, and adjustable clutch is a huge +. You can't adjust clutch strength on SRAM comparable models, leaving them with a lot of chain slap - Never had an issue with my XT chainslapping.
Also - VERY DURABLE. Took a minor hit to the derailleur by clipping a tree mid-air. Bent the hanger... picked up a new hanger and was good as new! was super worried the derailleur would have issues, but it was completely fine!