Anyone have any additional info on the Hornit? Thinking about getting one, AirZound is a giant fail for my commute as it stops working below 30 degrees even if pumped to maximum. It's not the air pressure dropping in the cold, it's the diaphragm in the horn itself stiffening or something. I tested this by putting the horn and the bottle in the freezer separately. Cold bottle, warm horn = regular "PHOOORNK!" Cold horn, warm bottle = tiny "wheet?"