I just got back from AES as well. I can vouch for the build and sound quality of both recorders. They're both very nice, but Korg missed out on a simple feature that would make them much more valuable. If the units themselves could act as a computer audio interface, bang- instant DSD sound card. Who's got a DSD sound in their computer these days? Oh well.
As far as why DSD, just look at a sine wave as described in 24/96 versus DSD. It's the closest thing we're going to have to a noiseless 1 inch analog you can slip into your pocket. I was about to drop a grand on the TASCAM HD-PS2. I'm going to wait and see now.
Cool forum, I'm finally getting back into field recording and this is a really great place.
Justin