Resolution audio Opus 21 vs. CD55

I like to hear any feedback from anyone who has listened and compared both CD players. From the spec, it looks like both players have similar components and construct except for the separate power supply in Opus 21. Thanks!
Could anyone comment on their sonic difference?
I've listen to them both extensively and would be happy to comment on the similarities and differences privately if you want to email me.
I am a Resolution Audio dealer. I have never heard the CD55, but I do have a customer who replaced his CD55 with an Opus 21 after doing a head-to-head comparison of the two over the course of a week. If I remember correctly, his initial impression was that the Opus 21 had much-improved bass over the CD55...then later told me that the Opus 21 was much better overall; more sophistication and refinement, etc.

He originally contacted me via Audiogon, so perhaps he'll chime in...