I'm a 5.3 owner and have had the opportunity to go to the factory in Raleigh. On the solid state end they developed the 5.3s with Sim Audio amps, so their integrated might be a very good choice. On the tube side they are very high on Art Audio and use these amps with their speakers at shows--don't know if they make an integrated though. Just thought I'd let you know what the folks at Soliloquy prefer. Best of luck.
Tim