Why u want internal battery for sure???
Man it's better with removable battery...
Adept is nice but u can't adjust the wattage I mean it's ok for zenith and zlide but what about the ares???
If I was you I would get a geekvape aegis or any other removable battery and a cheapo single battery charger with one or 2 batteries soon can swap them and never wait to charge...
Depending your country with that budget u can get that!!!!!
I know u said internal battery but just saying...
