yeah, they have a very particular way of doing things, but it is excellent and well-thought out. However, get ready for some nice heavy cabinets.
I might have a pair of 10" drivers up for sale soon. In my opinion, the best driver out there for a true 3-way. It the SS 25W/8565-01, I measured them and that's it, otherwise brand new. Looks like you may have other plans though...
Also, I'd recommend this forum for speaker building (and more importantly, designing). Extremely knowledgeable people there, and in my opinion the best forum out there for this stuff:
HTGuide Forum - Mission Possible DIY
Take care!