Test drove a few DACs over the last 3 months (Audiolab M-DAC, Chord Qutest, Denafrips Pontus II - on loan from a friend).....and heard the HoloAudio Spring 3 Level 2 that a friend owns. To my ears the Denafrips and HoloAudio R2R dacs were the best overall sounders, and I chose the Denafrips Pontus II over the Spring 3.....mostly because I got to demo it in my system. Chord had some amazing skills, but was too fatiguing to my ears....too much detail?
I have also used a Onkyo C-7030 and Audiolab 6000 CDT CD transports with the Pontus and have had zero issues