I can second many comments posted here already. I don't typically write reviews for products but I don't typically get something SO poorly thought out.
Both my fiance and I bought the same headlamp and both had the same problem with flickering light after MINIMAL usage. We used ours for one two-night backpacking trip and, thank god, only discovered the problem after we tried to use them after we got home. Upon quick research, lots of other people have had the same problem.
I WOULD NOT TRUST THIS PRODUCT.