Dual Voice Coil versus Single

ok, here's yet another question in my quest for bass in little as possible space...

My MTX Thunder 280 amp can deliver 80W RMS/channel at 2ohms, and 160W RMS bridged into 4 ohms.   So, would I be better off getting a 2ohm dual voice coil sub and pushing 80 watts to each coil, or getting a regular 4ohm sub and pushing the 160 watts to it?  Or will they be equal?

Thanks for any input!

get a single 4 ohm sub ....if you get a dual 2 ohm and wire 'em to each channel, you could blow the sub

i used to have a 12 inch pioneer diamond coned sub and its 160W RMS and it hits pretty hard .....my girlfriend has the same sub but mine hit harder cuz i gotta rodeo, and she has a 4 door integ.

now i gotta 10 inch infinity perfect and a bazooka el1500 mono amp and it hits hella hard. 

An note about the Thunder 280 amps,they usaully put out a good bit more power than they are actually rated at i.e. I had one of the thunder amps don't remember the model # but it was rated @ 40x2 12v & 60 or 70x2 @ 14.4v but it tested @ 78x2 @ 12v & 128x2 @ 14.4v.

man, I need to step up my voltage then, do you know how I can step it up to 14.4 for this amp?  Maybe a voltage regulator of some sort??? Thanks Static Revenger, i did notice the diffence in the advertised specs.