What would be louder/better?

I used to have 2 12" kicker CVR's wired at 2 ohms in a ported box with a ZX750.1 amp, it was a decent system before it was stolen. so, my question is, would one 12" Memphis MOJO in a custom ported box built by Memphis with a Memphis MR1200 amplifier wired at 1 ohm and a line driver be just as loud or louder? It's about the most powerful system that I could put into my car without upgrading the alternator which is something I do not want to do. I know it would be an expensive system to go with the Memphis route but I want to know if it would be worth putting down the money, and if it would be noticeably louder and sound better than my previous CVR's. Everything would be brand new if it helps much? and my car is a '95 Grand Am SE.