i don't think split piping actually reduces backpressure at all. The divergence would just cause turbulence, slowing the exhaust gasses and possibly even adding backpressure. Just a simple, straight shot out of the back of the car is the optimum exhaust path.

:edit: oh yeah, and if those pics are recent, the AC is still there. PS, i really don't mean to be a jerk, its a nice car, just giving my thots.