I've just got the 3" Golden Tee 2002/3 style Happ trackball. I haven't used any of the other types, and I haven't used mine loads yet (as it's not mounted in anything), but so far it seems just great.
I don't know but I would have thought the High Ball type would be slightly less comfortable for games like Golf/Bowling etc, where you strike the trackball.
Anyone got the 2.5" type?
I have both the 3" and the 2.25", but they aren't Happs trackballs. However, I am using Happs cover plates for both. If your going to use the cover plate you need the same room for the 3" as you do for the 2.25". Personally I like the 3" better. It just has a better feel and it's easier to get your hand on. If you're playing a game like Marble Madness, it's easier to get rolling in the right direction. You can also generate a longer spin using the 3".
So, I personally like the 3" better than the 2.25" for all games. And like I said "If your going to use the cover plate you need the same room for the 3" as you do for the 2.25"".
That's just my opinion, I could be wrong.

TM