In their early days DX just posted out replacements. But they have far too many customers to be able to do that now. they have too many "assertive" customers. Where I work, people calling themselves "assertive" get called psychopaths by the people I work with.
DX labels are quite distinctive and there are a lot of them when I have to go in to the PO to pick up parcels (i.e., every parcel DX sends tracked to me). Probably I'm the only one collecting torch stuff from my PO which serves about 100,000 people.
I don't like their bureaucratic procedures but they have always made stuff right for me - eventually.
To be fair there has been a problem about 3 times in 5 years. Yes, some of the stuff they sell is garbage which is why sites like this exist. The trick is to avoid the garbage, which if you tend to buy stuff on the day DX announce it can be a problem.
But is that DX's problem or mine? Read the reviews and you'll (mostly) be fine.
Problem is, a lot of the "first batch" lights will be sold out by the times the reviews are out there. Just see the wildly varying reviews on the Ultrafire C3 stainless steel lights. I have no doubt at all that all of the reviews are honest.
EU law requires a replacement two years later - though you are going to have to have a judge in the family to get this most times. I do.
Chinese law does not. If it works when it arrives and continues to do so for 90 days - well that's OK. If it dies within a few weeks I have reason to be annoyed. If it works for 3 months - well after that, that is why the prices are so low.
I've never had any free lights for review, and just about everyone else out there hasn't either. I think I'd take Matt's approach (Which hadn't occurred to me but I am very impressed with) and give away any lights I did get given for review.
That does lots for self-esteem.
I mean, a dubious review on a $20 light, or my reputation? I know how I'd choose.