Auto Parts: Air Filter, saturn ion, stock airbox

Question
My sister's birthday is coming up soon, and I want to get her an new air filter for her 2004 Saturn Ion 3.

I was raised around K&N so my first thought was, "No questions here. K&N."

But I realized that was simply based on everyone around me choosing K&N

Recommendations for an air filter brand to select would be appreciated!

The car is completely stock, and MPG is more important than power for her.

Thanks!

Answer
Andrew,

Honestly, I don't buy K&N replacement filters for the power gain.  There won't be much if any if you're still utilizing the stock airbox setup.  

Why I DO buy them, however, is mainly because I know I'll never have to buy another one.  I've got K&N filters in all 5 of my vehicles.  That's a selling point in istelf.  :)