The Naim CD5x performs better with the Naim Flatcap power supply, in my experience. Although if I needed to replace my CD player the Saturn R would be one that I’d like to audition.I like Naim CD players but the ones I've tried can't match the Saturn-R/DAC. The CDX/XPS was very dynamic and impressive but sounded very mechanical and two-dimensional. Something not right with the timing as well, sounded stilted.
Bought a CD5XS last year to see if it could better the Saturn combo. Poor thing, I felt embarrassed for it. It was so far behind that it sounded like a cheap player by comparison. I thought it might be better than the Rega is some ways but it was just a walkover.
I'd like to hear the Saturn-R against a CDS. I've heard various versions of the CDS often and I certainly wouldn't bet against the Rega.