What do you want it to do, that the standard airbox doesn't?

Im using the standard airbox on the Evo and its running 400bhp. It's not holding me back!

 

Oh im not interested in buying it - just said i noticed it and was interested to understand how it works!

I think from the general replies here though - it doesnt!!

I've already decided on the K&N one day when money permits!

It does make me wonder though how they can advertise these sort of things without any sort of benchmarks though - I mean, to market such a device they must have 'some' proof that it does what it says on the Family Circle tin?!