I saw about 40 minutes of DUNKIRK yesterday in DTSNX.
The sound is definitely very good. I could hear the overhead speakers when planes fly overhead, which I think makes it more interesting than just plan DTS-HDMA.
INTERSTELLAR, INCEPTION, and DUNKIRK all have pretty great sound quality.
So far I think the DUNKIRK in DTSNX sounds great.
For INTERSTELLAR, I did have to use my Yamaha phone remote app to easily and quickly boost the Dialogue Level (+2 or +3, I forget already).
That's one bad thing about some of these movies. You have to boost that Dialogue Level with some of these movies.
I didn't have to boost the Dialogue Level for DUNKIRK, though.