I got my first V-Link ~10 yrs ago (a 24/96 model). The DAC I had at the time, a Stello unit, ran on USB straight in from Windows XP desktop. As soon as I put the V-Link in the system and ran signal to the Stello via toslink, the sound became slightly less digital.
I upgraded the Stello DAC to the inexpensive but quite good Peachtree Audio DAC iTx. I tried USB straight in vs toslink, then coax from the V-Link, Again, it sounded better. Soon I upgraded to a V-Link 24/192 model + a significantly better coax cable (Oyaide DR-510), and there was a noticeable jump in quality: smoother, more organic, less edgy.
Then I upgraded the DAC to an Audio GD NOS 19 (a non-oversampling R 2R design considered "endgame" by some in the desktop audio/headphone community). That took forever to burn in, but once it did, I again compared USB straight in vs coax from the V-Link. Contest wasn't even close. V-Link + coax wins, as it always does.
And now I'm hearing some of the least "digital" digital of my life. No, it's not analog--rather, it's like some middle ground, digital that sounds unforced, organic, relaxed. I'm very happy with it--so much so that I picked up a new Audio GD DAC-19, the non-NOS version of the same DAC. It's burning in on my other computer, and it already sounds terrific...