I believe that any cotton filter of quality can be made to work without fouling the maf... BUT, I also believe that the filter has to be almost dry to achieve this... and then, they do not filter dust very well...

I'd stay stock... many dealers will refuse warranty paying for it if you have an oiled filter... I also have an Audi, and Audi owners have had the same experience.

Get a better flowing intake system... where I don't know, but a larger, better designed airbox with a larger filter would be the right way to go.. probably no space but...

Greg