Defy or an oil based stain?

15+ year old deck with cedar vertical posts and cedar top rails with glass inserts (floor is a solid surface covered with Gacco deck) in Seattle. Sun exposure on 75% of it in summer - lots of wetness in winter. Dry rot spots have been a problem. Original applications was CWF (oil?) and more recently CWF-UV (water based) in a cedar tone. Deck cleaned with oxygen cleaner and sanded to remove about 90% of the CWF-UV 'film' (lots of trim that is difficult to sand). Goal is to find a product that 1) does not film 2) less prone to mildew blackening 3) can be recoated every 2-3 years easily after a good cleaning. Only horizontal surface is 200 ft of top and bottom railing. I like the idea of Defy Extreme to minimize mildew growth but concerned about longevity and future reapplication. Or do I revert to an oil based product (TWP? Armstrong Clark? Acri Shield?) with a better history?