I bought the Pioneer sub thinking it would be able to fit underneath the 3rd row. It fits fine with the seats up, not so much with them down.
It'll fit inside the cargo area of the 2nd row though; not so much underneath.
I'd provide pics, but my 5 is still on a ship somewhere...
You could look into getting a Kenwood SW11 for the third row. You can run two of them simultaneously as far as I know.
My 5 has the Pioneer TS-WH500A; it's wouldn't fit below the third row seats as it's marginally bigger than the SW11.
I hammered the pinch bolt holder (not really sure what it's called to be honest, or how it broke off the strut) back in and torqued the bolt. It seems fine for now, but I'm still contemplating on getting coilovers.
Also... Found this... :(
Went out for a fun drive, until this happened:
Hit one bump and that was enough to make the driver's side shock to shoot down, almost ruining my CV axle and new tires.
I had to make an emergency stop since I smelled something burning, the sound of hitting the bump made me think I cracked...