At one time I had a pretty top level CEC transport to an external DAC. It was considered one of the best transports out there, and I could then use it with a number of different DAC's.
Then my buddies walked in with a stock Mac Mini and we A/B'ed it to the CEC transport. My CEC transport got crushed, big time. I mean it got blown away.
The next day I sold the CEC transport for more than twice what a new Mac Mini cost.
Then the mods to the Mac Mini started and it felt like we found another improvement every other week. That went on for months. There were bigger gains to be had there than with different DAC's.
By the time we were done, there was no way I could go back to spinning CD's.