I've had the DA-151 for a couple of days now. Before this I was just using the audio out of a very good motherboard (Intel BX2) plugged into a decent old-school NAD amp and some B&W speakers. So, I don't know how I tolerated it before, but now it really is like two layers of gauze have been taken off the speakers.
Of course I expected a significant improvement over onboard sound, so I was curious to hear how it compared to CD. I have what was once considered a very good Denon CD player, and I performed an A/B test using some favorite tracks (from Radiohead's In Rainbows - IMO there's no better band for A/B testing

). I listened to each track on CD first, pushing the volume to the loudest it could get and still be enjoyable, then did same with same track in FLAC with the Keces.
With each track it became increasingly apparent that there was just no contest. The sound through the Keces was more open, with clearer separation; detailed, more punctuated highs, tighter, more controlled bass. What really stuck me was how much better it sounded at louder volumes. Through the CD, the threshold at which the music turned into a murky jumble was significantly lower. Unfortunately I don't have the equipment or living conditions to really push the Keces sound further.
So now for the first time, I'm realizing I am going to have to rip my whole CD collection if I really want quality sound - that's going to be fun
Newbie that I am, I don't have another DAC to compare the DA-151 to. But as others have mentioned, it's very well put together, a solid and attractive piece that seems to be built to a high standard. I've paid a lot more for less. Also, it arrived well packed in 3 days to NY. Good stuff, Keces!