Shimano

XT Di2 SW-M8050 Shift Switch

While it's not the star of Shimano's electronic shifting platform, the fact that the XT Di2 SW-M8050 Shift Switch isn't hamstrung by the constraints of pulling cables means that—like with the XTR version—Shimano was able to build it with nothing but ergonomics in mind. Specifically, your ergonomics. The shift paddles can be customized to how you like them rather than forcing you to contort your digits to whatever design allowed the engineers to tease out the best mix of low weight and cable pull efficiency.

Though they're not actually pulling cable, Shimano builds the levers to provide tactile feedback on activation much like an indexed shifter. This is especially necessary on the XT version because it's part of a drivetrain that's meant for trail and all-mountain abuse whereas XTR is built primarily for XC racing. The increments in shifting are programmable through the E-Tube platform, and—if you're so inclined—you can run a single shifter with a double drivetrain and let Shimano's Synchronized Shifting feature manage your front shifts to keep you spinning optimally.