I now have about 120 hours on my URD. No problems reading CD disks (or CDRs). It did not sound too great right out of the box, but now is sounding really good. I have so far been using the SPDIF coaxial output exclusively, feeding a Denefrips Pontus II 12th.
This transport needs between 100 and 150 hours of burn in before making any serious observations. I have not noticed anything that sounds out of balance, or an emphasis in any particular aspect of the sound. At this point I like what I am hearing. This looks like a very solid transport, and I will eventually begin listening via the USB connection to see if there are further sonic gains.