Way late to the party, but an FYI for anybody considering the Gustard R26. 3 days is not nearly enough to break this thing in. When I got mine 2 years ago (as word of mouth was just starting to go nuts) I decided to try this out as it was less than half what I was looking at with Denafrips and especially Holo.
For the first few days, I thought it was ok, possibly better in the mids than my post-divorce "emergency" cheap AF Topping D90, but not amazing. I had 30 days to return it, and was starting to read people thought it needed at least 200 hours of break in. So, I let it run 24/7 occasionally checking in. After about 5 days the etch was gone, and top seemed a lot more open. I A/B'd with my Topping to make sure I wasn't hallucinating. After a little over a week, the main characteristics remained, but it was much, much more open and had incredible heft making my Focal Kanta No2's grunt with gusto. So really after 10-12 days it was 90% broken in and I was no longer concerned about my 30 day return window. It improved a bit more after that, but nothing to remark on.
At the time, I felt for $1600 I'd be looking at a replacement by now. Funny enough, not a whole lot has changed, the R26 still tops many lists. I demoed the Denafrips Venus in home before the Gustard and was pretty much sold, but prefer the Gustard and glad I took the risk. It's got a bunch of stuff I have zero use for, but for somebody that wants a flexible DAC with other features, hard to beat. I'm looking at getting my hands on a LAiV Harmony next, the build piques my interest, and again, $2700 beckons the cheapskate in me!
BTW, I mostly listen to my analog front end, I'd love to get something remotely close for digital. But again, I have a lot more invested in the analog side. having been collecting LP's since the late 60's.