The one benefit I see with the S550 over the BD50 is the 7.1 analog output (BD50 only has 5.1). Both players offer full decoding and Profile 2.0. Since you have a 7500, it would appear that you don't need the 7.1 output. Based on that, the two are a wash on features as far as your needs are concerned. Of the two, I am partial to Panasonic (have a BD30), but some of that is the lack of info on the S550 and a generally positive experience with the BD30.