wolo silver express air horns

Has anyone heard a set of wolo silver express direct drive horns on a vehicle? I've heard the sample on thier web site. http://www.wolo-mfg.com/truck.htm (http://www.wolo-mfg.com/truck.htm) They are rated at 115 db But that does'nt tell me how good they really sound on a truck. I like the real train horns that some people have. But, I'm not ready to install a on board air system yet. I just want the basic horn and simple compressor system that is deep and loud.
Thanks,
ecnar

Try googling Stebel Horns. I installed one on my motorcycle and loved it. Rated at about 135 db and cost less than 40.00.