Got one myself, here's my opinion,
Compared to a CA 650c, I preferred the sound of the cdp alone than cdp through Dac. (personal tastes maybe?)
Blu ray to rdac Optical in or hdmi pcm back to amp via analogue. I can tell the Dac is marginally better but not as much as you would expect. A massive difference is using the opitical out on the back of the tv to rdac, like you wouldn't believe. It's this margin I expected throughout but sadly no.
Usb is better than internal sound card by quite a margin.
Cdp is long gone and CDs ripped to laptop. Optical between tv and rdac sounds great, far superior to blu ray optical and tv analogue out. Don't know why it is, but it is. Its very clear, dialogue from blu rays sound crystal clear and films sound great fed into my brio r. If I put a cd in the blu ray and connect optical to rdac it makes a very good cdp but it doesn't have the same effect on films, pretty sure it's set up correctly too.
My question would be, why is blu ray optical inferior to tv optical??
Hope these ramblings make some sense to you, just read it back to myself lol