I don't know where you did your review reading - I'd read the 4520 owners thread
to find out more information.
You might also look at the Yamaha Aventage
line of AVRs.
Personally I think you could get an $500-800 AVR that will drive your Klipsch just fine. I sold a Yamaha HTR-7065
AVR to my nephew - he has Klipsch RF-52 fronts with the RC-52 center and RS-52 surrounds. That Yamaha does an excellent job of driving his speakers. The 7065 has preamp outs in case you think you don't have enough power.