The old Yamaha style. Not a huge fan. The thing I like with the current one is the target is large enough that once I find it, I can hold the mouse relatively steady and use the scroll wheel while my head is up looking at the stage without worrying about falling off of it. Anything that requires moving the actual mouse has the tendency to let you "fall off" the control and either stop being effective, or changing something you didn't want to, and you don't really have a sense of how far you're moving without looking down.
If I was just trying to do fx levels on a FOH mix, the smaller would be fine. If I'm doing monitors, I have no problem dedicating the one monitor to it. Honestly, between the channel strip and the knob farm, I don't actually look at the other monitor often.