Lots of people have had problems. My experience that that the MAF is touchy, and you must be carefule about over oiling the filter. In my opinion, there is a very fine line between over and under oiling the filter.

I get a bit paranoid about under oiling, used to race cycles, and saw what gets through if under oiled.

OTOH (on the other hand) I almost always get a seat of the pants increase putting in a K&N.

Why not try it and see if the performance gain is worth it? Start on the dry side, i.e. put the oil on evenly and sparingly.

IMHO, having a new SL, I don't want the dealer refusing to pay for a failed MAF when they see the K&N.

Greg