I included my past history with DACs and my system details. I think that context is critical.
I designed speakers as a kid and have hung out in audio shops and shows for decades. My digital hi-fi pursuit roughly started (in earnest) when I got a Musical Fidelity xRAYv3 - no slouch. I tried a Musical Fidelity M1 Clic to see how I liked streaming but noticed little or no difference. I eventually sold my xRAYv3 and dove into streaming with an Auralic mini & JRiver. Low cost, but the sound was great. A year later, I added a Arualic PSU. Nice and punchy DAC and untouchable at $500! The PSU took a bit of an edge off for another $300. More curious than anything, purchased a Border Patrol SE ($1500) a few years back. It is one of the worst measuring DACs you can buy but reviewers loved it. I attached it to the Mini streamer and noticed a nice step forward in performance, especially with things like cymbals and acoustic. I also did an A/B with a buddy's McIntosh DAC and it was VERY close to the SE. About a year ago, I upgraded my streamer to the Auralic Aries G1 (connected via SPDIF). The upgrade was very slight, but there. Not a lot of ROI on my $1900 purchase (used). Next came a demo of a $13k T+A MP2500 R DAC. This was the first time I could tell pretty quickly that there was a difference. Night and day? No. But hi-fi is a game of margins. It showed me that there is something to be gained out there but I was not about to drop that much on a DAC. I was on the hunt to do it for less.
Enter the Okto. I figured it would great to contrast the worst measuring DAC with the best to see where that got me. Well, the difference is not as great as you may think. They both sound very good. The Boarder Patrol is tad less resolving. After some time with the two DACs, it was clear that the Okto produced more realistic timbre and blacker backgrounds to give it the edge. The space around instruments is easy to pick out, as well. I would put the Okto on par with the T+A at a fraction of the price.
Finally, I tried a couple $5 USB cables I had around the house. No real change. I ordered a Wireworld Starlight 8 USB. I had been at a demo of a USB cable at a show years ago and could not believe a USB would make any difference - but it did. That was attached to a PC, though. My streamer does not have a power leg on the USB port so I again was skeptical it would do anything. I stand corrected, again. In my system, that was the last little bit that took any "digititus" off the top. I can't say it made the sound stage or tone different but it did take some sort of edge off allowing me to play more poor recordings without cringing and play metal music very loud without discomfort. Worth the $100? Yup. Once I heard the difference, I could not give it up. Commence the cable bashing ASR trolls. I have been able to notice slight differences but nothing huge (power/speakers/interconnects). That is my experience in my system. Your results may vary. If it is placebo, I'll take it.
For perspective, I have B&W 804d3 speakers driven by a Musical Fidelity M6500 amp in a dedicated room designed from the ground up as a 2-channel space. Room proportions are the golden ratio to reduce nodes. It is in a basement and has a very low noise floor.
Conclusion: I can't imagine that there is much more performance to gain in the DAC world. This is a GREAT match for my system in my room. I am a very happy owner who does not think I "settled" based on budget.
In case Okto is listening: You need to ship these things in a bag. Mine had a little moisture on it from shipping (condensation). Thankfully, no issues. The 5 month wait was slow torture but communication was good and prompt. It is clear that supplier delays are an issue. Hope you get that worked out so you can scale your business. It would be a crime NOT to get a lot of these DAC's out there. They are simply a great value and great in absolute terms.