Are the cans & guns standardized & interchangeable, or is it important to pick out a "reputable name" of gun to ensure a long-term supply of foam for it?
The wiki says:
When using a gun, the gun can be left on the can for short periods of disuse but must be taken off and cleaned if left for longer periods. Cans of cleaner designed to fit the guns are available.
Do the foam cans seal themselves well (like gas cylinders) when taken off the gun? Do you leave a can of cleaner on the gun when it's not in use, or just blow cleaner through the gun & then leave it open?