My overheads are around 5ft in front and 5ft behind the first row MLP. That is a bit further out than most people are doing Atmos, but I've angled my speakers to compensate for the distance and the lower ceiling. Plus, DTS:X (whenever I actually get the update) likes the speakers a bit further out, heck even directly above the front and rear main speakers, so this is the compromise that I've come up with and again, seems to get the blessing of several snooty "know-it-alls" on AVS.

If you have reasonable ceiling height (especially around the 9ft or more range) then straight down will work well. It is when you are around 8.5 feet or lower that angling becomes more important, with relationship to the distance away from the MLP of course. A lot of in-ceiling speakers designed for Atmos are angled at 30* (fixed angle), so there is something to be said about angled speakers if possible.

Farewell - June 4, 2020