Audiobahn Immortal Series

im suggesting you do not go near audiobahn.  Some will say they are the best, but everyone else will say they suck. 

How much you are going to spend on subs and amp and we all here will fit you with a system that'll be good.

Adires Shiva- http://adireaudio.com/mobile_audio/drivers/shiva.htm

Elemental Designs e12k : http://www.edesignaudio.com/ep2/12k.htm

Both these will give you good spl and SQ- more on the SQ side, but they are good subs.  I would make a ported box for them- slot port 

Then for amp JBL 1200.1 would do right.  Total would bring you below your spending range if you shop wisely i believe.

The only thing that Audiobahn products would be good for is a show-car that would never be started or sound system never used.

A friend of mine who buys and resells, bought a container of Audiobahn products and while he did make his money back, we tested some and blew at least 8 of the high excursions(I think that was the model) in everyones cars. And one of the amps started on fire inside. It kept on playing while his car started filling up with smoke on the freeway! I have a halon fire extinguisher in my car but he has a regular one that made a huge mess of his previously beautiful trunk. He just had to do a lot of vacuuming and carpet dying. I highly recommend a halon extinguisher to anyone who is into "safety" and doesn't want to make a mess of your car. Halon's starve the surrounding air of oxygen so the fire can't burn.

A.