I just got one of these. It's basically 2 EP4000s in one 70lb(!) chassis, spec-wise. Normally they cost $1000 online, but uniquesquared.com is selling them for $599. If you log in and apply the code: U2THANK55 you get about $50 off that price. Shipping is free.
A bunch of us on AVS just got EP4000s from these guys for $260 (that deal ended) and the service was good, got the amp quickly.
Anyway, I don't know what the policy is on posting these things, but for someone wanting to power a bunch of IB3s, this looks to be a great deal.
I'm going to power 2 4ohm IB3s off each side of the amp, wired to present a 8ohm load. This thing is specced to pump out 1200watts x 2 @ 8ohm, so it should be easy for it.