Dry film capacitor last as long as oil filled capacitors.

 Every weak dry film I've replaced was no more than 3-4 years old . I haven't replaced a oil filled that was newer than 30 yrs. old . Dry film can't handle heat like the oil filled ones can .  I bought a N.O.S. 400w M-59/H-33 ballast that had a weak dry film right out of the sealed box !  I have a few oil-filled caps that are over 60yrs old and still test within spec .