Another possibility to consider in the Injen CAI. To me it fits better than the AEM and is a higher quality piece. Also AEM is about to come out with their V2 intake for our cars, which is suppossed to have some pretty impresive gains.

As for this hydrolocking thing, I had my car in Florida for over a year before moving here and have driven in some pretty heavy rain storms, without any problems. The only time you would have to really worry would be going through deep puddles or the like.