Just received my D1 today and let it play for eight hours before I sat down for good listen. Ive got a smile on my face. First impression of build quality seems very good. As someone mentioned earlier, its ashamed that the digital in RCA was not of the same quality as the output RCAs. I guess for this price, its hard to really complain. I contemplated modifying my Marantz SA14 or adding a DAC and I think I made the right decision. I guess I can still have the mod done at a later date. Ive been very happy with my CDP which Ive had in my system for going on three years but after reading all the threads of incredible performance upgrades with the flurry of recent inexpensive DACs and mods, I caught a bit of the upgrade bug. I always felt the Marantz had very good redbook performance with decent bass, and a smooth midrange but I always felt that I was missing some upper frequency range. The Audio Mirror D1 does what its supposed to do with redbook playback. It brings bass to another level and now I have the highs I always felt that I was missing. I hoping that with a few days of break-in, the mids will warm up a bit. If things dont improve, Id still be extremely happy with my $500 investment.