induction or air

Hi all, The previous owner of my 330ci removed its factory air box and air ducting for some reason, replacing it with a K&N 57-0440 filter (no heat shield), attached directly to the MAF assembly where the airbox used to sit... You know the place - right behind the hot radiator and beside the...

to say the least i cant find any/meny spesificaly for my car, now i would like a good quality one but have no idea what is good (relitivly new to the who aftermarket bizzz) i know about pipercross and K&N any ideas ? mark