I've used the 5gal CRC and Gunk, they are kinda ok. I've never used the barrymore, i've heard it smells awful. My best luck is with the cleaner that you get along with alodine, i don't know what that stuff is but it is impressive! I don't leave stuff in there long because it is some kind of caustic and i preclean with carb spray befor i put anything in there because i want it to work on the tuff stuff and not just normal grime. Drop a carb body in there and pull it out after a few minutes and rinse it off and it is about spotless. I've seen it eat rust off the steel 2bbl throttle plates, like on a stromberg or a holly 94.