First impression: It feels good and it works as advertised. No anomalous aesthetics or mechanics. Vaped first 7ml tank completely dry (with much chain vaping and no dry hits) on 0.1 ohm nickel coil at 35 Joules and 420 degrees F.. The device's battery meter still showed about 3/4 of fully charged. I tested the batteries with a multimeter and both batteries (25 Rs) read exactly 3.67 volts. After shutting the system off, removing the Subtanktank, refilling it, re-mounting it and turning the device back on it remembered all the settings and worked perfectly. It's all good for me. Hope my black one works as well when it arrives.