In general, if you are setting up a pair of Fives as a stereo pair, the vertical orientation is usually recommended. But when Fives are set up as surrounds, either orientation will work. You should try both and see which one sounds (and looks) the best to your ears (and eyes) in your particular room setup.

For ‘music’ playback I personally prefer to use the Fives in a vertical position, with tweeters on the outside (slightly wider more diffuse soundstage), rather than have the tweeters on the inside (a slightly sharper stereo image), but I will also just add I much prefer to listen to a ‘stereo pair’ in front of me, rather than behind. So I have purchased an additional pair (+Sub) for that purpose.

For TV surrounds, I have long(ish) rectangular room. I have opted to put two Fives Horizontal, mostly because the Wife preferred the look of them in that orientation. I understand a horizontal speaker will output its ‘music’ audio over a much wider soundstage, but I’m not sure that applies/makes any difference when using them as TV surrounds.

I guess the answer is to try the different orientations and see which you prefer for TV/Music playback in your room.

Thanks for the replies! I’ll be mounting them relatively high (4m / 13ft) and most mounts support just one direction.

Maybe I’ll try them first and mount them later. 

Thanks!

I found for my larger area encompassing my dining room, kitchen, sitting room, and family room I much prefer to orient  them paired horizontally. Much better sound stage especially in areas that are farther away from the speakers