Thanks! What do you like specifically though?
I think I leave mine to default to 7 and medium. If I want a larger effect, I'll crank it up to 10 or 12 and adjust the LFE setting downward if there's too much bass. I usually only use the Auro upmixer for multichannel music, though to give it some height and make sure 5.1 surround albums like Alan Parsons' ON AIR album don't use the rear surrounds (He'll walk in a more "U" shape instead of straight across right behind me if DSU or Neural X are allowed to use the rear surrounds in upmixing and it wasn't really meant to do that).
I actually use Carver Sonic Holography (outboard decoder from HDMI analog & SPDIF extractor board between my NVidia Shield and the Marantz 7012) for 2-channel and sometimes Sonic Holography + Multi-Channel Stereo mode for a really "wrap around" effect that to my ears sounds far more natural than DSU, Neural X or Auromatic. But I do enjoy Auromatic for multi-channel albums to add some height to the effect (especially given surround before Atmos was expected to be mounted at either 1/3 or 2/3 room height, not really "ear level" so boosting the height a bit sounds more like I remember with my old 6.1 surround setup. DSU sounds worse than PLIIx, IMO and Neural X can be hit or miss (I find it works best with multichannel music as well; it can sound a bit odd with 2-channel for some reason, making things go too high up front, for one thing, but some multichannel music albums sound great with it also and more like Atmos music in some cases).
I read Involve Audio's Surround Master (now on V3) also does a great job with 2-channel music, but you need 5.1 analog inputs to use it (Marantz still supports 7.1 analog inputs so I've been thinking or ordering one to try it out, but at over $600, it's pretty expensive to test it out, although they do have a money back guarantee if you don't like it. It also decodes QS and SQ QUAD albums from the 1970s).
