No. It gets oil on the MAF wires. It does not filter as well.
I will 2nd the "No". I'm sure the oiled cotton filter element can flow more air and maybe catch tiny particles because of the oil, but in the long run, the K&N isn't worth the $ or the trouble.
Your ECU will compensate for the amount of air being let in past the filter; paper or cotton or other material, and the marginal increase in flow will not result in gobs of extra powwa. Don't let the in-store demonstration displays fool you.
As far as getting oil residue on the MAF...it all depends on how much oil you get on the filter. If you follow the instructions on the box, it shouldn't be too much of an issue. They (K&N) die the oil red to let you know where you put the oil. If you use it sparingly, you should be fine, but there is always the chance of over oiling.
The thing that got me was the cleaning of the filter; whether is was every 6 months or 12; if you do not have a filter to drop in the car while you are cleaning the K&N one, you cannot drive the car. You clean it hoping to not damage the filtering element, then you have to let it dry completely, and then once it is fully dry it can be oiled. So, you either have a "spare" paper filter to drop in while cleaning the K&N or you just don't drive the car for several hours.
For me, after doing to whole K&N thing on my (non-turbo) Mazda 323 LX, I found it was easier to buy good quality paper filters about every 12 months. I thought I was "saving the plant" and "making mad power yo" by using a reusable filter, but after several years of doing the K&N thing, I went back to paper filters thinking that my ONE paper filter wasn't going to hurt the planet, and how much power can a 1.6L 4cyl make anyway. Plus the paper filters were maintenance free - remove, toss, and replace.
I can buy 4 paper filters (4 years worth) for the price of the 1 K&N that will return negligible gains, if any. Yes, a K&N filter does provide an advantage, in racing, but I do not believe, any more, that it benefits the average consumer, unless you want to put the sticker on your window.
K&N = marketing hype, along with E3 plugs, Royal Purple oil, and Slick 50...