When u decide to buy the bells look on here there is always someone looking to sell.
I would only use the Nathans. As far as reliability, you wont find another horn that will withstand the heat, snow, mud, bugs road dirt like A nathan. And as far as heat goes mine see lots of heat under my truck and they never fail me.
Now everyone wants to be like me lol
i have since modified my system and use a paintball CO2 tank since they are rated for 900psi