The original Model S scroll wheels are not. They regularly fail to correctly count the number of ticks. Worse, you spend quite a bit of time staring at the dash computer trying to get them into the correct mode.
My first car had dedicated buttons, which was the correct design.
The fact that they don't accurately track the number of clicks is annoying, but I spend zero time staring at the dash to get them in the correct mode. My left is set to volume and the right set to AC temp and in the past year I've never felt the need to change that.
My first car had dedicated buttons, which was the correct design.