Mine get a once or twice a year cleaning I use light grease on the bolt rails with a light oiling of the other parts....I do change the recoil spring every few years.
I've never took my SBE's duck hunting so I can't comment on how good a boat paddle they make.

Honestly duck hunting is okay but when I hunt I like it to last over an hour or so...and ducks in standing timber are big targets and easy shots when they're decoying.