I have the RB25 system as well except I have the RW10 sub. I went with the Marantz SR7500. I paid 940.00 from an authorized dealer. You can probably get the 5500 for 550.00 from an authorized dealer. My Klipsch dealer was big on H/K, but once I was able to hear the Klipsch with Marantz, I changed my mind. The Marantz came with a 3 year parts/labor warranty too. Hopefully I won't need it, but I guess it's good to have.