Thanks for the speedy reply Bill. Here's my thoughts...
Q1 - gotchaQ2 - gotcha
Q3 - 4 ohm minimum load
Q4 - can I combine 16 ohm drivers instead of 8 ohm to come out ok? Is it better to run at 4 or 8 ohms?
Q5 - ...meaning 2 subs have twice as much mouth opening and as such, twice as much bass (chest caving levels!), correct?
Q6 - gotcha
OK - can you recommend good places to buy the parts (other than ebay)?
Lastly - I didn't mean to turn this into a BFM only topic: those were just the ones that seemed offer the best bang/buck. Is there any other system that's comparable, ie Bassmaxx or Pi?
thanks again