anyone have experience with tube cdps'

Your auditions with Rega and Cambridge should have impressed you with their layed back sound . I think they are overly polite and have the British Sonic. Musical not digital and warm.
You should do yourself a favor and stick with vinyl.
Of the three you want to hear. The only one I owned was the Audio Aero which I thought did an oustanding job retriving detail and still not harsh. Very tube dependent the Sovtek it camw with time with was painfully bad but a few rolls later and advice from my tube Guru led me to a great tube fot it a CV2943.

I did not find Rega laid back. In fact, the images were all quite large...as if it was trying to big-up the sound. I actually preferred the old rega Jupiter 2000 to the new apollo.

Go straight to the Audio Aero. Capitole MKII and MKIIse preferred.

PrimaLuna Prologue 8 with the upgraded board. Tube roll until you find the sound you like. SeeReview in TAS.

DG