Old CFLs?

How many harvests can you put CFLs through? Specifically 23w=100w soft white for flowering.

I think I have read opinions here that after a harvest it's best to change them....
Just a noob here so interested in what others have to say too....

Not sure but I know they dim with age. They are cheap enough I write a date on them and switch them after a grow or two, put them to household use and put some fresh ones in. Not sure if it accomplishes much but might as well have fresh bulbs when the used ones have utility elsewhere.

i have 3 year old bulbs that are just as bright as my new ones. guess it all depends on manufacture. i always buy the ones with extra long life to them. seems to work out best. all the cheap clfs i bought ended up goign out on me within a month or less. So i guess it just depends on personal reference ;>

They shouldnt dim with age since its a closed fixture (but dont quote me there). I've used eight 26 watt cfls for 3 grows now, and I've used my 125 watt cfl for 1 grow and I'm about to finish my 2nd grow with no problems.