Tried it, and a host of others. Wish I had all that money back. Plain old water works as good or better than any, is cheaper, and is traditional. Don't even have to add soap, or boil it. Lukewarm is fine, cold will do. Plug the touchhole or nipple, pour some down the barrel, slosh it back and forth and dump it. Most of the fouling comes out with the first go around. Repeat a couple of times, then a couple of wet patches, a dry one, and a lubed one and you are done. I think a lot of people over clean. Once the salts are dissolved most of the rest of the black color is just graphite anyway.