Just a FYI on how struts are, mine were original. But they "decay" over such a long period of time that you don't notice it. When I replaced mine (both front and rear) instead of just barely holding up the front and no longer supporting the rear both would spring to the stop and the rear clamshell would then open totally on its own after I released the latches. New ones really do make a difference.
PS. I never did get an answer on the shelf life of unused struts and whether having a spare set is worthwhile or if they will simply deteriorate from compression whether in active use or not.