If you are going to run a new XT M8000 11 speed drivetrain as a double or a triple, you have to run the M-8000 IL Left Shifter. Some riders will be building off a 1x system and going to a double or triple, or some will be replacing a damaged shifter. If you are starting from new, check out the right/left set. Either way the sharp, immediate shifts you experience with a new 2x/3x 11 speed DynaSys11 drivetrain will blow you away. When designing the M8000 system Shimano's engineers re-evaluated the already solid 10 speed version. Shift effort, indexing, and ergonomics all got special attention, as well as increased functionality in gear release. Mounting integration with i-Spec was also tweaked (and yes, we can hear the groans), but the new i-Spec II is cleaner and offers two-way adjustment of the brake and shift lever for optimal positioning. This is a real advantage for people with smaller hands or shorter finger reach.

To reduce shifting effort without negatively impacting a positive feel, the shift levers were lengthened and re-contoured for better ergonomics. This was especially crucial for the front shifter. Surface texture was modified for no slip leverage. Action is crisper and easier, and when combined with the provided, new OptiSlick cable, overall shifting effort was reduced by as much as 20%. The Vivid indexing mechanism improves on the already excellent shifting precision, crucial with the tight tolerances of 11 speed. Multi, Instant and 2-Way release all offer advanced shifting capability on the trail. You aren't limited by the controls, but empowered to shift as it works best for you in the conditions. In conjunction with improvement to the front derailleur and the stiff, perfectly sculpted chainring profile, you may not understand why 1x systems even exist when you can have the added range with such efficient shifting performance

It seems that the distinction between XT and XTR has been reduced again, and that the differences come down only to materials and weight. The excellent functionality and features of XT-M8000 can be found in the integration and focus on engineering that Shimano has built it's reputation on.