Well, KEF didn't waste any time with the R50 Atmos speakers.
They beat Revel, B&W, and most brands.
And it's the KEF R-series, so high quality here, not like some of the offerings.
So basically, you could consider the KEF R500/R50 a "modular" ATMOS tower, as opposed to the Pioneer single cabinet tower.
I think the modular route is most cost effective. If you don't care for ATMOS, you still get some great traditional speakers.
But if you couldn't care less for ATMOS, chances are you are NOT going to buy some ATMOS "enabled" speakers that "force" you to buy something you don't care for.
So sometimes "boxy" has its advantages.
B&W CM and Diamond speakers have those tweeters atop the speakers already. You can't just place another speaker atop that. B&W is totally screwed.
The Revel Performa doesn't seem to have enough real estate on top to accord an add-on like the KEF R50.
The RBH SX-T2/R definitely has enough real estate on top (13" x 19" curved flat surface) to allow an add-on ATMOS module.