Need Advice Quickly: MFW-15 vs F15HP

[Darksky]

First thank you for your educated input (Big Daddy, et all)
I am planning on building two Rythmik F15HP subwoofers. I have been working on plans and getting ready for the build. The F15HP kit is $729 +$60 shipping. Add to that the materials to build the box. Remeber I am building two. So lets say an easy $1,800

Last night a guy listed a pair of MFW-15 subs in cherry. He wants $750 for the pair. The kicker is that he lives less than an hour from my home.

What should I do? At less thatn half the cost - almost a third the cost actually. The MFW-15 pair is tempting.

I know that AV123 had quite a few problems. I also think that this particular sub had amp problems. The seller states that these particular subs are early builds. He bought them new in 2007. He also says he has not had any problems with the amps.

I have Focal 836V fronts, CC800V center and 814V as surrounds. The fronts are driven by an Emotiva XPA-2 and the center/surrounds by an Emotiva XPA-3

I listen to a lot of music (Oppo 93) I will say 50/50 HT/music. I am drawn to the Rythmik because they are supposedly incredibly tight and quick. I want my subs to compliment my L/R towers for music just as much as any HT desires.

Which way should I go? The room is ridiculously large 30x34 with 24 foot ceilings. I had initially considered a pair of Brian's F25 but he is having such delays with the new amp that he reccomended going with the F15HP pair instead.

Are there replacement amps available for the MFW15 from any other manufacturers? What about drivers? $750 is pretty cheap. I do have the money for the Rythmiks though. But is the difference in the two products worth the big difference in cost.

Also, the MFW-15 is absolutely without any sort of warranty.
Help me make a good decision.

Thanks again, Bradley