The gp1200 can be had for not much more than the gp760, but the gp760 is going to be easier to find at that kind of price. I would spend the extra money on the gp1200 over the gp760 given the 2-seater were an option.
The xl760 is going to be much more common than the xl1200 so of you are set on the 3-seater then the 760 is going to likely be the better way to go just because the xl1200 non-Pv is going to be very hard to find.
Power valve motors are more likely to fail. I'd take a gp760 over a gp800 unless the price is the exact same, because the 800 is much more likely to be a maintence problem. If you can't do everything to repair a ski excluding a motor rebuil, stay away from the 800. (I've never owned a Pv motor). Also everyone wants a fortune for their 800, 1200 and 1300 Pv skis, and they all have fresh motors, probably because they break and people think they can recover the money they just spent on repairs.
The kawasaki 750 is a good motor, so a 750 ss, zxi, etc would be great choices. I've ridden the as but not the zxi. If I were looking at the zxi, I would try to get the 1100 motor. I have not ridden a sts, but I had one I yanked the 750 motor out of. It was a barge and I don't think owning one, even with an 1100 would be very exciting. At that point, is just buy a boat.
