I've owned a DXG, and I sold it again. I had direct comparison to a K3 at that time (now I have a KPW, which has its own merits well beyond those other devices). As aesthetics go, everything was fine. And it was very nice to read books on it, I even prefered it to my K3 for that. In the end, however, the matter was that it was a bit to clumsy to transport. It was always waiting at home while I took the K3 on tour. At some point I decided to sell it again as long as I would get some reasonable amount of money back for it. In my case it even was a no-loss situation as I got my KDG for ~250 bucks in a special offer at Amazon and was able to get about as much for it when selling it as a used unit (I've imported it to Germany, which kind of created some benefit for german buyers).
I don't think I would buy a DXG again, even if it was down to 200 bucks. The form factor attracted me then because I thought it would be a good fit for reading PDFs. It was, but only to some extent. PDF based layouts often make assumptions that don't fit well with e-ink technology. I was much more satisfied later with a 10" Android tablet - being able to pan and zoom in an instant (and have color for the illustrations) is a really great thing. When it comes down to plain reading, e-ink still beats all other solutions.
Of course, all of these things, from aesthetics to use cases, are highly subjective and depend on personal preferences.