I am glad to see you are opening your eyes on cold air intakes and filters.
K&N does have a good idea and may be a better filter than some after market filters. But they require a lot more service to keep them working and if over oiled can give a lot of problems.
Here is some thinking on aftermarket cold air intake systems.
And if you still considering one chose it well.
Good Luck MT
There are a lot of different aftermarket cold air intake systems out there.
Most claim more HP and gas mileage.
But do they really give it to you?
And some of them are not even true outside cold air intake systems.
For normal driving I have found it is hard to beat the OEM air intake and filter systems.
Most of which are already forced cold air intake from fender or grille area.
Some ford trucks and some cars even have a cone shaped OEM filter in them
Performance people will claim that a add on cold air intake has less restriction
that gives them a few more HP for performances, which may be true.
Different engine react different but you also have to consider that the OEM intake manifold is also restricted.
And the fact that a lot of add on air intakes pull hot air from engine compartment instead of outside air from fender and grille.
Also a lot of oiled filters require more maintenance and care to keep in working order and gives MAF sensors a fit.