In terms of pure DAC performance this e28 is superior to the Datasat RS20i DAC. This is without any processing for either of them (meaning, no Dirac for the Datasat and no Dirac for the e28).
The sound of this DAC is so smooth and non-fatiguing it's almost creepy because I didn't expect it to be so good. It constantly has me turning it up more and more and I simply cannot get any pain out of it. I was even listening to it at 95-105db of constant volume at my listening position. Which as you would be aware, this is very loud. During peek movie explosions etc. it was pushing over 105db at my listening position and never hurt me or my wifes ears (I use all Active ATC speakers). It was the first time in my life, that I was able to create a massive wall of sound that was so loud I had to turn it down finally (notice I did not say painful experience or frequency causing me to turn it down). I mean, literally, there was just SO MUCH VOLUME that the room and us couldn't handle more volume. It's hard to explain this. I wasn't feeling "pain". I was just feeling that my body and ears cannot take any more volume. This was a dramatic change from all my previous experiences of painful frequencies etc. making me reach for the remote to turn it down, and then back up for dialog scenes.
I expect the e28 with my HTPC to beat the Datasat (which was my original belief as well) after applying the Dirac processing to it but that needs to be heard first (and all the filters setup as well). In respect of not starting a bashing war about the Datasat, I will tell you of all the demo's I have ever done it was the best of them all when the Dirac was engaged up to this point. The only ones I still have left to really demo are the Trinnov and the McIntosh MX151. But again, I suspect it will be in a step above come this weekend simply due to the fact that out of the gate performance (using only speaker distance and level calibration on both Datasat and e28) the e28 is the clear winner in sound quality for me and my wife.
However, it is possible that using Dirac creates a much more even response for ANY DAC or processor thrown into the mix due to how it fixes/corrects so many flaws. People are making claims that Dirac can make cheap DAC's and sound cards sound almost as good as the best of them out there. I will know for sure if this is true or not within 1 weeks time as I have an 8 channel DAC that is quite painful to my ears that I will be testing against the Datasat and the e28 to see if I can still hear a distinct difference between them all. If they all sound the same to me or virtually 95%, then it becomes to me more important who can provide me the fastest and best updates to future changes.