I bought the S550 for use the in bedroom as its much cheaper than buying a new reciever and a blu-ray player. The only issue I had is I don't have the bedroom wired for ethernet. I wanted to let people know that an old d-link DGL-3420 wireless access point worked great with the 550 using full auto settings on the s550. I was afraid it wouldn't work becuase I'd tried it with the PS3 out of curiosity before and had all kinds of issues and had to manually set the IP and still my PS3 would randomly sign me out. Works flawlessly with the s550 though. Make sure you flash the DGL-3420 to the newest firmware though.
Hmmm on second thought - when I bought the DGL-3420 they were only $60 or so - now I see the price is much higher so you might want to look at other options.
I've found most receivers priced below $1400 have fairly mediocre DACs. Often, better results can be had by using the Blu-Ray players analog out, providing it caters for the right decoding and the user knows how to set things up properly.