Not correcting, just explaining my reasons. In order to deal with my ceiling what with wiring and mounts (whether or not in-ceiling vs ceiling mounts), just not something I want to do in my living room where my main gear is. I may eventually convert a room downstairs into a media/theater room, that's where something like Atmos would start to be interesting....
As to your comment about DTS:X not being particularly based on ceiling speakers, will have to check that out as that's not been my impression but I really haven't dived into the subject since I'm not doing any implementing at this time. I know just enough to be dangerous