I think that PG is affecting me negatively, so I want to mix up some VG-based juice at least for a few days. Up until now I've just been adding a little VG to get more vapor, but now I'm using mixes with 60-70% VG and have some questions. Has anyone ever used more than one brand of VG and found one to be superior to the others? I'm just wondering if all USP-grade VGs are created equal. Also, the VG that I have is extremely thick. When squeezing the bottle, it takes 2-3 seconds for each drop to come out. PG in an identical bottle almost sprays out in a stream - I have to be careful not to squeeze too hard. Does anyone thin their VG in the VG bottle? I was thinking about adding some vodka to my bottle so that it's easier to use. Any thoughts on this? How do you tell if the final product is the right consistency/viscosity? What are the tell-take signs that an e-juice is too thick, or too thin? Has anyone ever tried to measure the viscosity of their final mix? How would you do that - both loosely and accurately?