I think it's solid, Dinny, but Ryan and Doug both complained of "fuzziness" a few pages back. After reading that I did a little test for my own satisfaction, playing a couple of tracks with fast, punchy bass lines on the TT and computer (using high-res rips of the same vinyl pressings) at the same time and switching back and forth on the pre-amp while listening.
To my ears (using both the HD800s and the Quads), while there were audible differences between the "pure" analog tracks and the digital files, there was nothing to latch on to in the bass region particularly.
Anyway, have them ship me that Naim DAC before it goes to you and I'll give you a nice comparison.