Joining in the discussion because I have been experiencing almost the same issues from day one. I wouldn't have thought to define my throat issues as burning but more like a huge lump however the more I think about it, that could be exactly what it feels like.
And now that you mention quality of nicotine vafromnc, you may have hit upon something. I thought I had it narrowed down to coconut, caramel, and sugar substitutes but maybe not. I definitely know my problem is VG but there is something else causing my throat problems.
I've been in to the doctor twice with a reaction and I find it odd that two different doctors have put me on Nexium and the next day, my throat is back to normal until I go back to vaping certain juices. This past week it was so bad that I was to the point of wondering... is this really worth it.
I would love to find out if those of us experience the same issue with the same vendor and flavor in order to narrow down the culprit because like many stated, it's getting too expensive.