I have a U-Hid set to quadrature on a Happ arcade trackball. Most games play pretty well, but I have to pretty consistently adjust Mame's default trackball sensitivity up by a considerable amount.
The game that I've had the most trouble with is Rampart. Even at the absolute max (255) sensitivity, the responsiveness is very sluggish and it's hard to place the wall pieces accurately. But I can play other games like Arkanoid and Crystal Castles quite well.
I managed to make it work reasonably well by running a utility called "interaccel" that meddles with the mouse driver and inserts some acceleration curves. I don't see anyone else needing to do this so I'm wondering if I'm missing something, or if people just don't play Rampart. Would be nice if Mame had more configurability for analog inputs.