unimpressed from United States, WA Public Profile

And probably the most important thing: I repeatedly read and researched on the internet before plugging the USB charger into my computer. The MH20 manual confirmed USB use with a computer so I followed the instructions. My computer had a 550W power supply and the USB was connected to it. After a couple hours the new Nitecore 18650 Battery (2600mAH NCNL186- purchased separately) did not appear to be taking a charge, so USB was unplugged from the computer. The computer, which had operated flawlessly prior to this, now would not power off. I now find that the computer has apparently 'crashed and burned' as all efforts to salvage it have so far failed.
THINK TWICE BEFORE PLUGGING THIS UNIT INTO YOUR COMPUTER!

After waiting a couple weeks for an out of stock item I received a unit with a switch that functions intermittently. Looks great out of the box with really nice accessories included. (thus- 2 Stars) The rechargeable NITECORE 18650/2600mAH battery (ordered separately) has been fully charged with the USB and I find that the MH20 'special' functions are erratic; the switch does not seem to access the modes as the manual describes and the 'half-switch' position is not positive. After checking all this out it has now decided it does not want to work at all. Taking the head off, removing the battery and re-assembling it will usually restore most functionality but all the above irregularities are still present. Apparently the NITECORE MH20 'smart-head' is defective.
I recently purchased a STREAMLIGHT LED that I am very pleased with and am thinking it would be wise to stay with STREAMLIGHT in the future.
As usual OPTICS PLANET is a first-class operation and I am sure they will remedy the problem.