They were ending up VERY VERY similar looking. A bit more noise in the manual shots, but not objectionable. And I think that might be due to my settings - I tend to keep the NR turned down pretty low to get more detail and figure I can always apply more in PP if I want to. I suspect that in EXR-SN mode, the camera over-rides your settings and probably applies more NR to the shot. That's the only explanation I can come up with because the camera was choosing essentially identical ISO and DR settings in both cases. The only other thing it MIGHT be doing is essentially exposing more to the right and then tamping the exposure back down in processing to get less noise? Which I could do as well, but I haven't experimented with that yet. In any case, they were coming out close enough that I'll probably just go forward with it like that until and unless it starts to matter. And for really really really low light shots, with static subjects, I can always flip over to the Pro-Low Light mode. I don't see doing that much in the flow of shooting, but if I"m taking a good hard look at something, I might...
-Ray