Gilly:
No, I have not decontaminated one. I just read about it and am willing to try it if I need to. I don’t know why the MAF won over the MAP, I’m sure there’s a good reason, I just hope it’s not profit in the replacement parts dept. Yes, it looked like a chunk of plastic, but there was the strip semi-hidden within it. The zener diode is 100% exposed and at first glance it appeared that was all there was to it. I thought wtf, maybe it’s a magic zener, but then I saw the metal strip. I still have no clue why the zener is exposed like that.

EuroCoupe:
I hear ya. I think most stock cars could care less, but also factor in that most of a paper filters life is not spent fresh and clean. The K&N really shines when it’s dirty, meanwhile a dirty paper element is choking the motor out. I see a lot of dust where I live, especially in my chevota because it see off-road action. If I put a new paper filter on it I will feel a significant loss in power, but no loss in my K&N covered with filth and ½ the pleats literally filled with dirt. In fact, I gets so dirty so quick that I use a pre-filter most of the time. You need to be careful with those too, only one type can flow enough to match the K&N, and you guessed it; a K&N brand pre-filter. 

Some engines just like being stock, any changes and it will hurt performance. Example; some lose power with a freer flowing muffler. Is it the mufflers fault? No, the problem most likely lies in the fuel delivery and ign timing. All engines will make more power if they can breathe better, but they need to manage that extra air to do it.