I agree with the plate amp, but build your own box if you can. I paid a whole $20 to make my subwoofer cabinet. Not pretty, but quick and cheap and painted black. If I ever decideto finsih it, it still won't be nearly as much as those cabinets.
FWIW, I use a BP1201 and that plate amp in a home sub for my father in law. He was impressed, but I think I was more so for the money.
Edit: very nice, Dave. Yep, they kind of make you look like an ass. Hopefully they will make some improvements soon.