Totally unnecessary unless you are boating in a sand & gravel pit IMO
Inland lakes for now,and will be in some areas that are prone to dusty conditions.
Greetings,
What I've read on off road sites; K&N filters are just a step above chicken wire for filtering efficiency. As mentioned we have what appear to be shop vac foam filters on our Lehmans. If ever faced with dusty conditions I would probably opt for aftermarket paper filters as some of you have.
And rivers are subject to dirty air from farming and yes the sand & gravel pits. I imagine near shore conditions are reasonable similar.