I've seen worse, I used to install sounds straight from my garage and man, sometimes id get the ghetooest d*mb @$$es comin' to me tellin' me their sounds werent poudin' right, Id see the radio and wires crossed. 10 gauge positive wire running though the door exposed wires everything and 1000 watt knock off amps on no name brand 12's.....whew I thought I was then only that had seen bad installs.....
Wow! He should get a patent for that enclosure. He could call it the "Sub Trunk." I don't really know much about car audio, but could his back seat start on fire if his amp gets hot enough?