I seriously researched one of those when I had my single-pup Fender. I think with one of their switching pup-rings it'd be pretty sweet. From what I saw and heard, the P90 sound as well as the humbucker in series and parallel sounded pretty cool. The rails single coil was just OK, although it sounded pretty cool in the middle position of a two-pup guitar with both of them set on the rails.