The locking plugs aren't really coming out. The speaker will get knocked over or they will break before they pull out of the binding posts. This is why I no longer use the locking ones on the speaker side.
I actually did flip my terminal cups upside down so they angle down too. nothing but wires attached to mine, so it isn't an issue. Better check those ones if you do because there may be clearance issues if the x-over is mounted to the cup.