air filters? Options

[TSiwrx]

if anyone has ever seen an oem intake system on a 300zx, they know what i am talking about. right now i have a big box in between my headlights that is sucking air through a small inlet on the bottom of the box. i am sure the two k&n dropins help, but i am also sure the bored throttle bodies could use some more. is there really any hard evidence that one air filter is better than another? im sure there is, but in purchasing an intake for the Z, all the tops name brands and their kits were kinda pricey. i ended up buying a MAS adapter from HKS and am planning on buying my own filter. HKS filters are foam as well as GReddy, k&n filters are that oiled gauze, Blitz filters are sus stainless steel mesh, is there really a difference between all of them? in terms of price, performance, and longevity, what are your opinions? thanks.

[TSiwrx]

i thought i remembered HKS not being very good, yet a lot of japanese tuners still use them, but APEXi filters are used all the time on the majority of the skylines i read about, im still undecided as of now. i remember reading somewhere that with those APC cone filters as soon as you put them on, they become dirty then are a hinderance to your engine. so i dont really want to end up with one of those.