That is the 1000$ question. Most people rely on the brand. Those no-name 500 pieces sets from the big box stores are generally overpriced scrapmetal. I only had bad results with tools made in China.
Some easy tests:
If the tool has a rubber handle, try to smell and feel it. If it has some "chemical smell" or it sticks unpleasantly to your hand, the tool is definitely junk and the plasticizers from the cheap rubber will transfer through your skin.
Same:
- It has some imperfections on the surface.