Recently upgraded my DVD player to a Pioneer 575 and dumped a Yamaha nsp 320 sub sat combo for Mission M7DS rears and M7C1 centre, to match the Mission 701s that I already owned. All I need to do now is upgrade my AV receiver, a Yamaha RXV 420 - what should I get to match the Missions? what is that maximum amount worth spending? A the YAMAHA RXV1500RDS looks a bargain from Germany but even for £430? would it be wasted when connected to the missions?