As far as water getting in I can tell you that I drove through an absolute torrential downpour one night with no problems. I mean it was raining so hard that even with Aqualpel (PPG's better answer to RainX) and the wipers going full I couldn't see more than 20' in front of me. I mean it was pouring. No problems. I have also raced it on the track in a moderate rainfall with no problems.
Now if you try to cross a river with it... good luck. Otherwise, I think the rain in the intake theory is just that... theoretical.
+1