As with all speakers, the speaker should be mounted so that the tweeter is at the same height as your ears when seated in your normal listening position.
For my RL60s, I originally wall mounted them so I didn't purchase them with stands. Later I purchased some speaker stands (non B&O) and adapted them to hold the speakers.
Since that time I have, on a couple of occasions, contemplated getting some 'proper' B&O stands from eBay but each time I have changed my mind as I don't think they look as attractive as mine. Although I do accept they are made for my speaker and probably more stable.