This stuff does exactly what it says it's does. Keep an eye on the time or set a timer if you have to. You'll want to spot check it to make sure of how it is working on what you're using it on. It's pretty great, a little goes a long way. It pretty amazing actually, I'm not sure if there's another product that is more heavy duty, but if there is, I'd definitely stay away from it,because this stuff is great. I used steel shot to polish after running pieces through this,and the results were pretty amazing.