r,
I have two and frankly I use that over the twist

It holds 4.0-4.2 but don't have an 'underload' meter.... I run a 1.5Ω cisco on it for my espresso
vape - perfect! for that flavor. I like the fact that it has the eGo-c protection as well whereas the earlier eGo one didn't. (although I never had that one heat up - btw, I did have an eGo-t heat up on me last week - close to the too hot to touch area - I ditched it - it was on a good, imo, charger although I'm watching other eGo-t's that I have now

)