Ever since you first posted about this I've been keeping an eye on mine. I'd say with comparable builds/wattage, the Abyss does use up more battery than a Mixx, a Supbox or a BB (clone - sevo 70 board), but not much. Not 30% more in my case.That’s with light vaping - that time of day I’m kind of busy. I would generally expect to see it down to around -30% after supper, if I’d put the battery in first thing in the morning, as I normally do. So closer to 9-10 hours.
And no, haven’t tried with the 21700 yet, I wanted to see if it was just that one 18650 or if I could repeat the results with another one.
We need @AngeNZ to buy one so she can do some scientific experiments in her vape lair.

