Well with all due respect IMO the current Supermicro IV is the best period. This should blow everything and then some.
Ray's amp are fantastic, he is a great guy with great service and super fast shipment. His amps are built like a tank and sound great. I currently own an SR71 and a Tomahawk. However as I stated above the current Supermicro IV sounds better so there is no guessing since it has already happened.