I use the three positions roughly equally depending on the application; I probably favor the bridge the most, but all get used. I voted for split because it is the most unique and I love it for clean tones.
I use the bridge and neck equally, bridge for overdriven rhythms and neck for leads. I use the middle position for most clean sounds, though I sometimes use the neck for that. And then there's the piezo...
I use neck and bridge usually..
but if i'm on clean channel I'll never use the bridge pick up, I think the d sonic sounds awful in clean mode..I really like the center position on clean