TBH, the 3200mAh rumor is more believable, since it's removable and there's not much space for a big battery as you have to fill up some of that space with a cavity to house a battery.
On the bright side, this is a 200mAh upgrade over the V10, which is a nice thing especially since the G5 went 200mAh down in terms of capacity compared to the G4. Considering that the general hardware is overall more efficient than the V10, battery life should improve above the 200mAh capacity bump.
And I've said the same for the Note7. The Snapdragon 820 and 4GB RAM combo is more than fine. The LG G5 performed pretty well with that combo, so I don't see why the V20 will be no different, unless they rushed their implementation of Nougat, which I don't think will be the case.