I went the cheap way with my Fujita F5 and rigged up a half dome clear plastic around my filter and it's been working great. I even cut out the fake vent in front of the filter and had it meshed for the ram air effect.

 

Damn, my old post ressurected after all this time!! Like Liquid Ice, I dont have alot of experience with rain. My car is garaged and rarely driven in the wet or on overnights. I do have the drain hole plugged and an ebay heat shield over the filter. Seems to be fine. BTW - Liquid Ice's link is the best one going that covers this issue.

 

Great Choice

I'm in a similar predicament. I never drive in the rain, but after one event I found there was a spontaneous storm right before I left. I was very concerned driving around on the wet road, surrounded by puddles.

 

I don't drive it in the rain either but, you never know when you might get caught up in a situation. I figured I just have to do it once and it'll be a while before I have to take it out to clean. Oh, and looking through the vent to see the F5 filter looks damn good too because the plastic has the same curves as the filter so it doesn't look ghetto