Most converters these days are decent enough for most people, especially if you aren’t making money with your music/engineering. As others have said, it’s a case of 5-10% improvements most of the time. I’ve been using the Antelope Orion for the last decade or so for my main conversion to and from my mixer but for my mastering setup and main monitor DAC I have a Lavry blue system. I experienced a very noticeable improvement in the Orion when I clocked it from the Lavry. I think clocks are where the real improvements can still be made, considering most converters are using the same chips these days. Listen through this vid and see what a difference a high end clock can bring to medium level converters:
I’m toying with the idea that I can replace my RND MBP with the MBC as I really only use it for the limiting these days and have access to the stereo field stuff from my M/S equipped eq.
Edit: could be worse, here’s Lavry’s high end A/D and D/A…$16,600 before tax 