The one with better DACs is definitely the one to go with, but these days, from what I understand, the DACs are all pretty darn good at turning the 1s and 0s into music.
I can't hear much difference when I use RCA as opposed to coax or optical for my CD sound reproduction, but others may have better ears than I to pick up on some of the subtlety...
On the other hand, if your receiver is doing any processing, which it may or may not do in your 2 channel set-up, consider keeping it in the digital domain for as long as possible. After all, when your receiver futzes with the sound using DSPs, it has to convert the sound back to digital and then use its DACs to send the sound out to the speakers.
So, you might be decoding, re-encoding, processing and then re-decoding - compared to just processing and decoding. Those two extra steps might lead to some compression of the sound or other decoding errors (fuzz, hum, pops, etc.)
Try both and ese which you like better. As another poster likes to say "trust your ears"
