This review compares the Master 3 to the Master MX 2S. I've used the MX 2S for a couple of years. It seemed the perfect mouse for me. My only complaint is the rubber-like coating on the wheel. It's meant to let your fingers grip the wheel better, which it does. But the rubber-like coating irritates my finger tip, as if I'm allergic to the coating. And since I am allergic to latex and rubber, the rubber coating may very well be causing this reaction.
I bought the Master 3, which don't have a rubber-like coating on the wheel, to see if it won't irritate my finger tip. Well, that question is moot, since I immediately found the Master 3 narrower than the MX 2S and comfortably so, as I couldn't wrap my hands around it, as I could the MX 2S. And the "hump" below my palm on the Master 3 is uncomfortably lower than the one on the MX 2S The forward and back buttons are re-positioned on the Master 3, which I didn't like, but I suppose I could get used to it. And there is only one LED on the Master 3, as opposed to the three on the MX 2S; I like my LEDs. But my greatest dislike about the Master 3 is how its wheel has a pronounced bump when you roll it, which I find jarring and unpleasant. The "bump" on the MX 2S is more subtle and gentler. (I know the wheels on these two mice could be changed to roll freely, but I need the "bumps" to better control the wheel.)
As for whether the rubber-free wheel on the Master 3 irritates my finger tip, I can't say, since I quickly returned the Master 3.
I'd wish Logitech had offered a "Master MX 2S Version 2," which is the same size and design as the MX 2S, but without the rubber coating on the wheel. Unfortunately, the Master 3 did not work for me. But I suppose your "mileage may vary."