I use salt nic, that adds a bit of flavor, even at low mg. Over 70% vg can be overly sweet too, so maybe go higher pg would help you too? I actually had a bottle of sour, but gave it away to a friend trying DIY, so I can't tell you how effective that'd beI'd love to go unflavored but I tried it a couple of times and the taste the nic and the sweetness of the VG make me gag. I wonder if a bittering additives I've seen on the flavor vendors' sites would at least remove the sweetness of the VG?