Opening the hood scoops is personal preference. If you drive in the rain at all you will notice that the leading edge of the hood get's a little wet but from there back the rain will blow over the hood not on it. No water will get into the openings. Even while at a stop, very little water will go in through the openings and the air cleaner lid and intake manifold is about all that will get a few drips on them. (Usually when you open the hood to check is all)

Brett!