In my opinion this efest Newest Efest 35A IMR 18650 2500mah flat top rechargeable battery perfec for ecig-Efest battery for E-cigs actually out performs the Sony VTC5 regardless of the sub ohm down to .2.
I also use the 2014 15A Efest IMR 18500 1000mah 3.7V rechargeable battery -Efest battery for E-cigs and Newest Efest 10.5A 18350 700mah purple high drain 3.7V battery flat top-Efest battery for E-cigs with my .8 to 1.2 ohm kayfun builds or even a higher ohm build on a rda. I would say the EFest purple batteries are as good as anything out there regardless of who makes them, that is as long as you get a legit efest purple battery.
I also use the 2014 15A Efest IMR 18500 1000mah 3.7V rechargeable battery -Efest battery for E-cigs and Newest Efest 10.5A 18350 700mah purple high drain 3.7V battery flat top-Efest battery for E-cigs with my .8 to 1.2 ohm kayfun builds or even a higher ohm build on a rda. I would say the EFest purple batteries are as good as anything out there regardless of who makes them, that is as long as you get a legit efest purple battery.