Re: Luna as Surrounds mounted horizontally?
Are you mostly music or movies? If movies, I'm not so sure how important timbre matching is, particularly for heights/Atmos, as this is usually just effects and not sure if one could hear a difference.
To address Curtis' question, I don't think there is a spec for height/ATMOS speakers. Most multi-channel AVRs might give 60 wpc for heights/ATMOS.
Personally, for sides/surrounds/heights, especially if mainly for movies, I don't think one needs to go "overboard" with expensive speakers. The HTM200s work really great for these channels, even paired with RAAL-equipped speakers.
LG OLED65E6P, Anthem AVM70, Rogue RP5 and ST100, VTV Pascal 7 ch, Ascend Acoustics Sierra Towers with RAAL, Horizon with RAAL center, Sierra 2 surrounds, and HTM200SE front & rear heights, Rythmik E15HPx2, miniDSP FLEX RCA, VPI Classic 1+ (VTA Tower, Fatboy Gimball), VAS NOVA, Soundsmith Paua, Manley Chinook, Bob's Devices SUT, SugarCube 1 mini, Oppo 103D, Oppo 203. Audio Sensibility and Blue Jeans cabling, Symposium & Isoacoustics isolation products, GIK Treatments.