Just a thought....I spent many years leaving my hard earned treasures in their cases, only taking them out when I needed them, as a result they are still in pristine condition, (that "my goodness, this is beautiful" moment - every time), but under used.
so last year I took all of them out and now they are ready to pick up and play, which I do much more regularly, they are dusty (but I do dust them) and they are open to the heat and knocks....
I now prefer them being out, but long to have them back in to keep 'em lovely
How about you?