I'd probably go with the E-power if I were comparing the Kgo and the E-power.
That said, this video shows an AW 18650 IMR battery with a voltmeter and a dual coil carto right off the charger dropping under load to 3.47v. The 1100mah eGo battery held at 3.8 or so using the same DVM module and dual coil carto.
I don't see that on my Provari using 2 ohm or 3 ohm cartos. I have the same DVM module. Of course, the voltage I see on the DVM is boost regulated, but the voltage test built into the Provari checks the battery under load, sizzling the carto while the voltage displays. After vaping a couple of hours at 4.2v on a 3 ohm AW 18650 IMR, I will typically show 3.8v true battery voltage under load. I haven't tried it using a dual coil, though.
I couldn't see whether the AW battery was a 1600mah or a 2000mah.