I have a one chamber.......................................................
It's louder than some open pipes that I've heard.
If you are bozo, it's definately handing cops their PC to stop on a silver platter. If you have a bunch of cops in your area that look for people to stop and you ain't their best friend, stay away from the one chamber.
On the other hand, due to it's size, it doesn't take up a lot of space.