If you over-oil it, sure. But if you prep it properly, it works just fine. And bonus: it's reusable. However, I just went with a paper filter from a'pexi because JDM, yo. Or because it's just what I found first on amazon.

I mean a good intake like the grimmspeed will give you a little bit more power. So if money is no object and you want the ultimate NA build, then go for it. But for me, the $/hp was much better with the drop-in filter.

Catalyst are made for the environment. For me, Canada requires one. If a cop stops you. He tow your car and you can only drive the car with a cat.