My new (1st) model S arrives in a couple weeks. With respect to autopilot. 1st - I assume using auto pilot in heavy rain, and certainly snow, is not a good idea. Lane markings need to be visable. I would think a light rain might be O’k. 2 - Sensors on front & rear bumpers, camers on fenders and B pillar need constant attention, i.e. after inclement weather, car wash, and summer buggy weather. I always carry Windex in my vehicles. I would use a micro cloth, or something as soft, to clean all such sensors when anticipate using autopilot, or in any situation a sensor might activate. Comments?