I've heard PG has a stronger hit than VG, and I heard it's solely relative to nic-MG. From my own experiences, I've bought many juices from different vendors with various bases and nic concentrations, and the TH was always relative to the specific juice, not concentration. Most recently, I bought a bottle of 100% PG Tobacco at 18mg from American e-liquid, and it literally has no throat hit. It tastes nice, but it's hard for me to vape a juice without at least a medium hit. I thought I was going to get knocked over with the 100% PG...but I guess I was wrong. So.......really, where does it come from?