In my experience it is true that Unity struggles on older computers, or perhaps where the graphics driver situation isn't great. I've had a lot of installations

In my experience it is true that Unity struggles on older computers, or perhaps where the graphics driver situation isn't great. I've had a lot of installations where the dock takes 5-10 seconds to load. Agree with you about ease of use though, people seem to pick it up quite quickly. For the basic functionality of opening and switching applications, people seem to pick it up almost immediately. Not quite the same for using the dock, but even so.