I just had John Tucker of Exemplar Audio upgrade my Oppo 105 and to say it is stunning is an understatement. Now the cost to upgrade is more than @2K "but" I would compare it to a Meitner or much higher class DAC in a heart beat. You will have to spend somewhere between $15K or higher to beat this unit. I owned the PS Audio PWD MK2 and my upgraded Oppo 105 is on another planet from that. I like this because now the Oppo 105 is one unit that does everything. I removed a DAC and a digital cable from the loop and run direct to my integrated. The only stand alone DAC I would be willing to try would be a Lampizator, however, I would want one of the higher end models. I was told the new Amber is a great bang for the buck but have not heard it.
There are others upgrading the Oppo 105 and probably do a great job but John's would be hard to beat.
There are others upgrading the Oppo 105 and probably do a great job but John's would be hard to beat.