Cage nuts - which way to insert them?

I've always done them horizontally, because that way you always have clear access to the tang with a screwdriver. If you install them vertically there is potential for good access to the tang to be obscured by equipment above or below, or the top or bottom of the rack.

I suspect it is far better to place them horizontally, so the flaps are in the direction of the force of gravity.

I suspect if you think of it like corrugated cardboard, the flap kinda looks like a single corrugation, then you might see what I am trying to say.. When push on the cardboard from the side it is far more likely to collapse, but if you push on it from the top, it is extremely sturdy.

If the metal uses was extremely weak, or the gravitational forces (weight) acting on it was very strong, it seems to me that the lower flap of the vertical orientation, might bend inward a bit resulting in a cagenut that falls out of the slot. Whereas the

I suppose if your rack had any reason for some side-to-side force acting on it, you might want do it the other way.