How long do good speakers last?


I just ordered a set of Sonus Faber Olympica Nova Vs, my first foray into nice speakers. I turn 51 this month and am hoping these will be the last speakers I ever buy. But it got me to thinking - how long should I expect these speakers to last? Or any good speakers for that matter? Does the foam eventually break down? Issues with general wear and tear? Appreciate your perspectives!
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Vandersteen model 1B player the crap out of them 25 years long. Fortunly they have the rubber instead of foam edges an they have a abuse circuit that kicks inn if needed. When aging an lately applied room correction they sounds better an better.
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My 1989 PSB stratus gold's have Butyl rubber surrounds. They have never let me down. I even called and spoke to a tech about if the crossovers needed to be recapped and was assured these speakers should last longer than me.
I think you might be ok with those SF speakers.  My Olympica 3 are probably 7 years old and going strong.  I think 20 years is achievable.