This is my favorite shifter to date and I can't imagine smoother shifting.
I came from a 1x10 with a OneUp Components 42 cog and the shifting in the middle gears wasn't great. It worked, but it wasn't crisp. When the Shimano XT 1x11 group came out, I jumped on it and bought this shifter because the XT one has the ugly meter on it. This XTR shifter works perfectly with the XT components.
Shifting became a dream, but after using it for one month, I crashed and the thumb lever completely broke off. These things happen, but what's unfortunate is that Shimano doesn't sell replacement parts for this shifter, so if you break a part, you pretty much have to buy the shifter all over again...which is what I did. For that, I give it 4 stars.