I have a knock-off of durafix. Have not tried the stuff yet ($52 for 1lbs). Gave a few two a friend to try as he had a project to use them on. The if used right, it is supposed to work well.
I have tried Aluminators and gave them away (was not impressed).
Also guy, these are O/A (gas) solutions, not for TIG, but they do work. I have seen a live demo, and I bet they guy had done it 100,000 times before, looked so easy.