Methinks GeorgeS should go into the Speaker/subwoofer business.

I thought Frantz put it extremely well, and did not belittle DIY in the least. DIY certainly will save you lots. George, I think you should also mention the the pride you'll feel from doing it yourself!
But we all have to decide what to spend our time on. I don't have the room to do that kind of work, have enough tools already and don't really want to get into woodworking - I don't have enough time for the projects I already have. I prefer to spend my tinkering time with my bicycles - my idea of a hands-on project is to build a set of wheels. I just don't want to have to learn enough about matching drivers to volumes, ports (or not), and then wonder if I got it together right the first time. I'm willing to talk Q-factors, freewheels, gearing selection, drag brakes or not, etc. Some people just want to ride their bike - others may just want to listen to their music.
DIY is a fine answer. In time, if I get the right place, I'm retired and bored, maybe I'll want to build my own - may even try an IB to see how it turns out. But two years ago, living in an apartment, I was just glad to find what I did at the pricepoint I did. Never been disappointed, never felt cheated. Got what I expected, and more. (hey, at least I assemble my own cables and don't pay retail for them!)
But if you want to go DIY, you've still got to wade through all the anecdotal information out there - which plan or kit is the right one? I certainly don't know. And if I go through the expense of building it, will I be happy with what I did, or should I have tried something else? Do I have the right parts here? Heck, did I get the stain or paint on evenly? Was I impatient, put it together to see how it sounded, then took it apart to do the finishing and stripped out the screw heads just doing that work. There *are* frustrations that come with DIY to match the pride.
I was willing to pay their price for the ability to return it for just shipping costs, let them worry about the fit and finish, add a warantee (which they've shown they are willing to honor even when it looks like someone abused the poor beast). Much better than another company who who builds "the lowest-tech piece of 'equipment' this side of a pile of rocks," but won't back it up. That's something.
Eric
P.S. Mr. Bunge, you certainly have my respect as well.