I was planning on recommending a XR57 to a friend who needs a very compact, inexpensive ( <$300 ) receiver for 2 channel music only. Size is the main criteria for her. Also didn't see any replacement receivers to the 55/57. I am out of the loop as well. The current panny AVR BX-500 is 6-1/4" tall which is too tall for her. the XR57 is only 4-1/4" tall and runs cool. hmm.
ed