I was informed directly by AW that there are counterfeit AW IMR 18650's on the market. Based on my testing, i believe the counterfeit battery to possibly be a Unprotected lithium ion chemistry, not the chemistry of a IMR. Unprotected lithium ion batteries, if shorted, can have catostrophic failure.
I was sent one of the counterfeits and was able to load test it vs. a real AW IMR 18650. I tested at 2.5 amps, which simulates the load of a LR 1.5ohm atomizer. The AW held up to .2 tenths higher voltage under load and recorded an actual tested mAh of 1513. The countefeit did not hold voltage under load as well (down up to .2 tenths voltage) and recorded an uncharacteristically high 2054 mAh (rated at 1600mah) and displays a graph very similar to trustfire/ultrafire lithium ions i have tested.
Real AW IMRS have a protruding button top, not flat top. Also, the AW sticker on the Real AW batteries is slightly larger then the fakes and the wrapper is a bit deeper red and the font slightly thicker and darker on the real AW's.
Real AW IMR on Bottom, Fake AW IMR on top: