I’ve got a variety of 2” and 3” in our various airplanes, and honestly don't even think about which is which most of the time. I prefer the 3” in the planes in which I routinely fly aerobatics just because of the broader surface where you’re in contact with the webbing. For the shoulders, you can get the same effect with harness pads. In my littlest cockpit, I have 2”, and find that works well because otherwise its just too much webbing in the way of other stuff.
In all cases, I prefer rotary buckles because they seem more secure, and less likely to get snagged and accidentally released.
Paul