The 963 and the C50ES (does the C50ES have TOSLink optical input?) are priced similarly, and I want a reasonably good quality receiver for a bedroom / computer setup. I'm interested in the 763 because of its low price - furthermore, it's basically the 963 without redbook upsampling. Redbook playback is very important to me (which is why I'm hesitant about the 763), but a good internal DAC is the most important - I'm going to use my PC as a transport to one of these units. I have very few SACD's at the moment so that isn't very important, either. DVD playback / picture quality would be the least important.
I may or may not get an external DAC later on - either a dAck or a SN TubeDac(+?). I was actually hoping that the internal DAC would be good enough (or could be upgraded enough) to compete with either of those two DAC units so I could save some money hehe. Which is why I'm so interested in the Philips 763 / 963 - I believe there are several good modifications I can make to the DAC section, am I correct?
I'm looking for warmth and musicality - I already have enough (cold) analytical detail in the rest of my system.
Of course, if there's something better within the price range, please feel free to make that suggestion.
Edit: And I forgot to mention: main setup would be a SS, analytical headphone system - a mid-fi speaker system is the secondary one.