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No sacrificial gear here either. But then I have never dove anywhere that the crew sets up your gear so that hasn't been an issue. At most they check air on or assist if requested. Shore diving Bonaire is tempting, things can get pretty beat up that way. But over the years I have become less concerned by cosmetic wear but still just as fussy about maintenance. The only thing I'd say that I still baby is my Petrel.
Alternate gear for different dives and reduntant dive gear, yes to both. I see that as different from the op's definition of sacrifical gear. All my gear gets the same care.
I have yet to experience any incident that I wished I was NOT using my own gear since first certified. I have one set for rec and one set for tec. Scuba diving is a expensive recreation sport already.
I have some really really old Sherwoods I use in the pool or let my kids use there. I used to segregate beach/boat or shallow/deeper like you are thinking of doing but have re-thought that idea. It's life-support gear so I use the best I have at that moment in performance and reliability. It sure would be ironic to suffer a tragic failure with the beater stuff while your brand new mint condition A-1 super-duper gear is gathering dust in the garage.
Your heirs might appreciate inheriting the good stuff though.
Yeah, sometimes I do cringe when the good stuff gets whacked about. Like the first ding on a new car.