Just a brief report, didn't use auto setup, just set speaker size and LFE crossover freq. Low freq effect feel better than my old marantz sr7002.look forward to detailed setup later. Btw, i am using kef speakers in all 5.1channel. Will add a pair of front height later. I use my Denon pma 1500ae as power amp to drive front channel. So i can't give detailed comments for 2 channel performance. And, there is update for the 4520. But not really sure what have been updated.