i wouldn't mess with a drop in filter either. They just let more dirt in, with gain of about nothing.
My MAFv testing done by myself on both stock vs KnN have proven, they don't flow any more to even be picked up by our stock MAF, which is fairly sensitive.
I used to run a KnN for the first 40K of my car, and every oil analsys i sent (blackstone labs did the testing) in came back with high silicon content. This means DIRT in my engine oil. THeir suggestion every time was check the air intake system for leaks, welp i have no leaks, only a KnN. FOr the last 10K i've been running a stock filter, and have sent my last 8K oil change interval into blackstone, now i'm just awaiting what i suspect will be much lower levels of silicon (should have the results any day now).