I've been using the AW IMR16340 550maH 3.7v batts for a few days, and I must say I'm impressed. Got these to be "just a little safer" and it seems to me that they last almost as long as the 750mah ones, and very little drop off in power. They almost seem to make the GLV2 vape smoother as well, which I have no idea why that would be. All I know is I'm loving these, and just ordered another 6.