behind the seat sub?

Ok so here is my delima. Ive been fighting it for about two years now. I drive a 96 tacoma regular cab. The age old question whats the best boom i can fit behind the seat. I'm 6'2" also so keep this in mind. Im trying to find a pair of subs to fit behind there that can handle a good amount of power (1500rms / 750ea) i have multiple setups looking for the best SQ but still beat down the street. I have had two soundtream RFW12s with 1kwrms in a sealed box that posted in the 135s on tl. this setup sounded great and slapped but was just too big and i couldnt slide the seat back as far as i would of liked and the surrounded would rub and at some points almost rubbed holes. After that i had a set of RE Audio SE 10s in a 2cu ft ported enclosure tuned to 34hz. which in my opinion sounded like doodie with the same 1krms to them. they hit LOOOWWWW but didnt actually make a lot of noise just shook the doodie out of everything. I was thinking along the lines of two tens or 12s in a sealed enclosure now with a little more power. OK so the question which subs would everyone recommend. the big thing is the room behind the seat. i can gets about 5" mounting depth. 5.5 would be pushing it.Got Slap?

The amp i will be using will be the Hifonics BXI1606D. and one of the subs in mind was the Elemental Designs 11kv2 woofer. its rated at 600rms per sub. and to be honest i think that hifonics wont put out much more then that with my charging system. and it fits the bill with only a 5" mounting depth and its ideal sealed enclosure is only .5 cu ft.Got Slap?

pioneer makes a slim fit flat sub designed for the kind of situation you are in. not sure of the specs on them. i have heard them before tho and despite them being pioneer speakers they  didnt sound half bad.1 12" mtx 9500 4ohm dvc 1 8100d and 1 1501d almost loud enough to cover the sounds of my car dying.

i looked into these a bit already. the same elemental designs makes a slim woofer, both just dont quite reach my power handling requirements.Got Slap?