All that I can say is I bought a small tub of it years ago and have used it on several occasions with good results in several firearms. I also own a Lewis Lead remover and have used it a time or two as well. Never had the need to purchase any refills though.
I used the JB's on surplus and other second hand bores as a starting place in the initial cleaning to get the crud out at first and although I can't quite do it on a regular basis found out that I really will scrub somemething out of a barrel that has been cared for since new.