I have a 2002 996 coupe and use only OEM Porsche parts. Your car is
under warranty and I would stick to Porsche parts while it is.

I've heard mixed reviews of K&N style filters (the oil-coated, reuseable
style that supposedly flows more air to the engine and increases
performance) from both Porsche and other car owners. Some claim there is
a performance gain, others don't. ( I ran a K&N on a 1981 280ZX Turbo
and noticed no difference). The negative side is some claim the filters
don't remove the tiniest particulates that a stock filter does, and they
have suffered premature wear or outright engine damage as a result.

Just the rumor the aftermarket filter might miss some fine particles was
enough to keep me using Porsche parts.....