Here's my front set up.
Yes, those are RP-280Fs with Atmos up speakers on the side. RP-450c in middle.
I had the space in my loft to have put in a 175" projector screen, so the speakers look tiny in comparison.
Moving RP-250s' to side soon.
Need to get back speakers but debating RP-280F's or RP-180M's in back since have bookcase in back would hold them at ear level and feel that the floors might be mostly pointing at back of couch, which seems wasteful (front are 14' to couch, back would only be 4' on floor, 5' in bookcase)
Jay