To "goodysgotacuda"s points, I think the best thing to do is start with a budget. Then buy the best you can for that amount. But a used "name brand" is probably better than a new "no name". The "no name" craps out you throw it away. The name brand craps out you get it repaired.

That said, I have no problem with cheaper items like the Harbor Freight auto darkening helmets - I used one for years until I scored a killer deal on a high quality helmet. I still keep the HF unit around for visitors.