Quantum DAC and Cesium Transport

Does anybody know much about these two older products by Resolution Audio? Compared to CD50 and CD55??
I home demoed them say 7/8 years ago. Good stuff;but not to good at the price point of the time.Stereophile gave them a class B rating..Was my feeling also.It aint no giant killer by any means.
Robert Harley hated the transport. A good feature was that two dacs could be used in a stereo configuration with their adapter box. They are outdated but you can see if Quantum will perform upgrades to them.
No upgrades are available. Also note that Ultra Analog is out of business so in the unlikley event that the chips go bad replacement is difficult. The transport in the Cesium is likewise no longer made. An "orphan" product although Resolution Audio is still in business.

The Quantum was a damn fine DAC that was compared to units costing much more money by Robert Harley ($3,000 versus $6,000+) -- he unfortunately got hung up on Resolution's recommendation that *TWO* DAC's be run in a balanced configuration (only possible with the pricy Cesium transport). You can do this now with any transport if you can find a Chronos (Resolution's anti jitter device).

Anyway, the Quantum on its own was a bit of a giant killer in its day -- considered better than the EAD 9000 and close to the then top of the line Sonic Frontiers. This is one of the most puzzling reviews I've read. He describes the DAC's qualities, favorable compares it to much more costly equipment abd then pans it. Go figure. Anyway, a good DAC for current re-sale prices.

Suggest you call Resolution Audio for a more informed opinion.
I would like to state further-I had at the time Theta's pro basic2.(2K)The Quantum (3.4K) dac was on par with 'IT'.I kept the Rez.dac for about 3 weeks.I finally exchanged it for Gen5/+(450.00), before the a mod came out.Brand new with 2 day's breakin ;sorry,not even close.So I repeat giant killer,my FOOT. Don't believe all you read.How this compares to the new 50/55 ? - never heard them. There was a reason Theta got an A rating,and a reason the Quantum got a B.But one should always listen at home yourself. The used price reflects the differences.
Thanks for the responses. I'll contact Resolution Audio and see what they say.