I bet the difference will be in the amount of decoding each player does as we see today with cheaper DVD players passing the uncoded bitstream to a decoding receiver vs. more expensive players that have internal decoders.
I'm still curious to hear what kind of difference there is between regular Dolby Digital and DTS versus PCM or DTS-HD. As far as I can tell, plain DD/DTS sounds pretty fine to me. But then again, you don't know what you're missing until you hear it I guess.