I do not watch a lot of movies, my collection of Atmos BDs is very small. Of that small collection, the movie Hacksaw Ridge is very convincing. So much so, that when the bullets fly, it is hard to avoid the instinct to duck and take cover.
What I do find is rewarding is the performance of the Dolby Digital Surround up mixer's ability to produce a very natural facsimile of original acoustics from two channel sources. I find this remarkable. I have never localized to any of the four ceiling speakers, or the others for that matter, unless a producer puts a definite voice on a surround speaker for instance.
I think there is some misunderstanding of the principles underlying the Atmos technology. It is based on orthodox 3D coordinate geometry using x,y and z coordinates.
Every pin point location in any room can be defined by those three coordinates. So the objects, a bullet for instance moves as the x,y,z coordinates change instantaneously over time as the object moves. So the sound of that object moves as the power to all speakers changes and directs the movement.
Now what this means, is that for this to work optimally, all speakers must be in the exact positions specified for the system you are using.
So, I set this room up with all speakers at the precise Dolby specifications, to the absolute letter. In addition the speakers really need to be consistent, especially the fronts, surrounds and rear backs. The ceiling speakers should be as neutral as possible. I have the advantage here, since I am the designer of all the speakers. After doing this for so long, I am able to make my speakers have extremely similar tonality and acoustic presentation, even if the drivers are different. This is to me at least is by far the most difficult aspect of speaker design to master. However in a multichannel system it is crucial I believe, for optimal results.
Having said all that two good speakers can provide 90% of the loaf. The rest is incremental benefit. I am far from convinced that having more than two or three speakers in an open plan room provides any benefit whatsoever.
That is a huge problem for domestic systems, as getting really good results, does require a dedicated space designed for the purpose. This is seldom possible for obvious reasons.
I have said this many times, that two or three really good front speakers is going to give far better and more convincing results than 11 mediocre ones and especially poor ones. Even at that, the center speaker is so problematic that two speakers is often preferable. If you do use a center speaker, then it takes over as being the most important speaker of the lot. It is by far the most difficult to design, and in my view needs to be a highly specialized speaker designed for that role.
I can attest to what I have said, as I have a 2.2 system, a 3.1 system and a 7.2.4 system. But the I could easily live with the 2 channel system and for that matter even do without the subs. It is a very pleasurable system, and I listen to it a lot in the winter season.
Lastly I truly believe that adding poorer speakers implemented badly by poor position, for instance, sets your system back. I am certain there are many, many systems that would be better off with less speakers.