The hand dryers are bad but predictable. The auto flush toilet nearly derailed potty training for two of my kids. We had to go back to pullups while on vacation at a popular theme park because of them. We did find some restrooms that did not have the auto flush toilets and he was able to keep the pullup dry. I once had the experience of one flushing while I was on it. I can assure you that I am suspicious of them as well.

My Son refuses to use Public Restrooms. He'd prefer to hold it in and wait until He gets back Home.
I wish that I could have Him tell Me why, but being 'Non-Verbal', He can't.