Ah cool, I didn't know it could do button combinations too, that's clever.
I'm happy with my trackball too, I think that for a DAW it's a great input device.
I'm also firmly of the belief that mice have their place, as a (former) competitive gamer I would NEVER use a trackball to play my shooters. (Just like using a controller btw, you simply don't get the speed and control you can have with a good mouse.)
So it all depends on what you use it for, but as I said, for a DAW a trackball is great.