Not bad... as saagarjha says, you can slide on either that key or the brightness key. Unfortunately, that doesn't work for me because I've set the touchbar to default to F-keys for the sake of consistency with the other keyboards I use. For whatever reason, this means that the slide-on-button trick does not work.

For me the physical keys are better. With the touch bar, I have to look down to change the volume, and it occasionally hangs with the volume slider visible, but not actually responding to input. That's usually when I really want to turn down the volume quickly, and instead my laptop is blasting for another second while I have to adjust the volume with the mouse.

Also I really would like a physical mute button. It's often very valuable to be able to mute in a hurry.

The thing is, you can't use the touch bar without looking at it whereas I was constantly blind typing function keys. I think Apple have a different understand of "Pro" than I do.

You slide on the virtual key.