Originally Posted by mcnarus
If it works, you're getting the same 1s and 0s from a $100 deck that you would from a $2K deck. Anything more should be for extra features unrelated to sound quality, like style and build quality. I have a 20 year old Yamaha that was built like a tank and is still kicking, and even that was only $200. Nothing wrong with spending a little extra for something that looks nice, either, but I suspect you're not willing to spend $1900 extra for a pretty faceplate and a slightly sturdier mechanism and case.
Another feature you may want is optical out, which just lets your AVR do the analog conversion instead of the CD player, but it's not necessary - the DAC in the CD player will likely be just as good as the DAC in the receiver. The only other thing that may push it higher is multi disc capability, anywhere from 5 to 400. Sony has made a 400 disc CD changer since the early 2000s at least, and they also make a 400 disc DVD player for basically the same price ($300-400) that's the same form factor and will play CDs just as well.