Rain X is a great product, no doubt. I had it on my Edge and my F150 before that and was very pleased with how the water beaded and rolled right off, usually to the top of the window because of the wind helping push it up.
I really do love the rain sensor wipers and how they operate. I have never had any of the problems you have posted, or if I did, I must not have thought it was a problem? But I do leave my sensitivity set pretty high so that might be a part of it. Only problem I have had was a random sweep for no reason under what I thought was a clear sky. Maybe it has happened two or three times over the last four years with the two different cars, but still not a problem.
Only other negative I would think about the rain sensor is if you forget to turn them off when using a drive through car wash where you get out of the car. I seldom use one, but have remembered to shut them off so far.