Hi everyone - I've been offline for a week (yep a real vacation) so a little late to responding to some questions that are right-up my alley.
@totalwex and @canibefrank - I use the Impact Monitors with dual subs. Check out my system page. I've talked about my experience with them quite a bit. There is also an Impact Monitor thread going here on Audiogon.
@craigl59 - I've always used Paypal. Yes, you have to pay a fee but its worth it. Audiogon has gotten a lot better recently so I would insist the transaction stay totally within the Audiogon system including all payment and tracking information.