On my coach the Tri-Mark keys for the bays are double cut, they can be inserted eitehr way, and they work either way. Don't matter.
Door keys are single cut (one way only) won't go in the wrong way.
One other key is double cut as well (This one for a switch I never use, it kid-proofs the slides, I have no kids to proof)
I do, however, have an opinion of Tri-Mark locksets... I won't exactly say what it is but let's just say they are "High maintenance" and leave it there. I fix too many of them.
And I only work on ONE RV... MINE!
Home is where I park it!