I look at this like I do my dirt bike. I don't buy a new air filter every time I ride it so why buy a new air filter for my rc every time I drive it.
I clean mine with PJ1 air filter cleaner for foam air filters available at any motocross store and use Maxima air filter oil. Which comes in a spray bottle
If it sticks enough that a 450 can't suck the air filter dry then an rc won't.
Plus you get ALLOT more air filter oil for your money using the maxima stuff.
Oh and about Drake and RB saying to put a new one every time well Drake gets them for free and RB wants to sell more stuff.