Yeah, Chad's got a good point. Buy them at Circuit City. They have a policy that states if you buy a speaker you have one year to come back and upgrade. If you don't like the one you bought you just pay the difference and get the better one. So if you get 2 TypeR 2ohm/coil (SWR1221) subs and later you save up and buy the second MRDM500 then just go back and ask them to trade them for the dual 4 ohm (SWR1241) subs.

That's how I do it and I work there