You don't need a "lifter" --- that's more for racing.
Buy the Look p15. It's similar to the bomb proff p18 world cup binding. The majority of guys jumping on Look bindings roll with the p18. The p15 is easier to find, usually sold in retail shops, and the classic look design. The PX is similar to any standard binding, and the lifter will give you less response while skiing park. The P15, however, incorporates the pivot technology with turntable heel. This technology works on the premise that the longer your foot stays in contact with the heel piece, the more protected the skier is against knee injuries.
I've had the p18 world cup binding for a while now, never broken a pair, and never pre-released when my skis should have stayed on. Given that the PX version operates without the turntable heel, I think you should shoot for the p15 while searching for bindings.
Good luck searching for bindings