Occasionally I do power up and exercise them just to ensure the functionality of the mechanism. Also to clean the surface from moss/fungi as my country is hot and humid.
You can visit my minidisc collection as well. http://stereo2go.org/forums/threads/minidisc-small-collection.301/
Your set-up is like walking into my dream store. But I see no prices?! I guess if I have to ask.....I can't afford them.