Here is an interesting take on two channel vs. Atmos. This reviewer, having just reviewed the new top of line Martin Logan Monoliths, concludes with comment that the Atmos offered a more realistic sounding presentation. Most interesting is that the author used music he produced, so is likely the one best positioned to make a claim such as this.

Skip to the end if you don't care about the ML review.

Martin Logan vs Atmos

Certainly time will tell and opinions vary, but just an interesting take.

Primary: MD600, MS200 (SpeakerLink to AES), Trinnov ST-2, Ayre V6-xe, Salk SS8 3x LRC.
Secondary: MC600 (whole house).
Zone one: 568.2, G57, MS200, Spatial Hologram M2SE.
Zone 2-6 (Awaiting assignment).