I have the Mountune cold air intake and think it's excellent, it's the metal version of the OEM ST200 one. It's the first one that
@Zormecteon referred to in Post #3 above. It gives you some nice extra sound, and maybe a bit of extra power,especially when used with a tune, which I have in the MP215.
I want maximum filtration even though I don't live on a dirt road and will not be Rallycrossing the car, so my mechanic came up with a great suggestion. I'm using the OEM paper filters for maximum protection instead of the oiled K&N type filter which came with the kit, but replace them once a year which for me is at about 3,500 Mi. so having them for maximum filtration doesn't compromise airflow by having the filter get clogged up because they are replaced so often. I believe they only cost about $20 at Rock Auto, so it's not a great extra expense. The ST200 CAI came with the OEM paper air filter, so that also gives me a good feeling about using it.