You can't buy the materials for the per-box prices I see on the web site. But from what you say about shipping, you're talking 3X the price of the box. On that basis you can invest $100 to $120 in material per box. I think that with that kind of budget ($200 to $250 per pair) you can build substantially better cabinetsOTOH, if you have to buy tools too, obviously the pre-made cabinet is the better buy. Have you looked at Parts Express? They now sell pre-made cabinets that many people have said are very nice for the money.