Don't underestimate them either. That said, I've tried the multiple LED lights as well and have no love for them. I noticed in a side-by-side comparison that a dual LED light had about the same light output as a single one and figured that the LEDs can't really draw enough current from the same sized battery to be effective. However, single lights put out much more light than 250 lumens. I know what a 250 lumen light looks like and what a 600 to 800 lumen light looks like. And, as I said above, I've compared the Chinese lights to lights with a known output and they are as bright...and even a little brighter...than the more expensive light. I will grant you that the lights won't put out 1200 lumens but they put out more than the 200 lumens that the article you linked to above.

As you said above, they have a very good light output for a $20 light. It's far better than what you'll get for most any other $20 light. It's better than many $60 "be seen" lights. The MEC light suggested above is $24 ($30 US) and has a 90 lumen output. Even the (incredibly low) light output measured by the We Test Light website is much brighter than that for the same money. Yes, 250 lumens is a dim light but it's still better than 90 lumens. 250 lumens is getting into the "seeing" category instead of a "be seen (but not really)" light. The more realistic 600 lumens that these lights put out gets into the "see and be seen" category even in urban areas with lots of other light sources.