It depends on the source for sure.
Sometimes NeuralX sounds better when watching DTS movies, sometimes DSU sounds better.
Sometimes they sound about the same.
But for me in general, when I watch DTS movies, I use DTS NeuralX.
When I watch Dolby movies, I use DSU.
When I watch PCM (not DTS, not DD), I use DSU. But I think for PCM, NeuralX and DSU sound about the same most of the time.