I've thought that when I get air horns, I'm not going to link them to the main horn button at all because not every situation demands the noise of air horns. For times when you're just giving someone a little toot (to remind them that the light has turned green, etc...) the main horn is plenty, but if someone is doing something unsafe (backing up and going to hit my truck, driving 20 mph in a 45 zone w/o warning lights on, etc...) that's when the air horns would come into play.