As per mcMaddy I’d suggest not putting any coating of any kind on your windscreen. There’s not many things more irritating than squeaky juddery smearing wipers and a coating is highly likely to cause that. The wipers work best when the glass is just clean with nothing on it.
Actually - a tip for getting your screen spotless and wipers working smoothly - “Silvo” metal polish. Youll get it in a supermarket for less than a fiver. Very effective.