PG has a better throat hit and carries flavor better. VG produces more vapor, but reduces the thoat hit and reduces the flavor. The higher the nic, the better thoat hit. I know some flavors seem like they have a better TH, not sure if stronger flavor would increase the TH, but I could see that it could maybe?? if 18 is not doing it for you, try 24. and if you want the best possible TH, then do 100% PG, but most people after they've been vaping a while seem to like to mix a little VG in there. 20% VG, 80%PG seems to be the most popular, but its all personaly preference. There are TH enhancers out there, like vape wizard. Also putting a drop or 2 of pure menthol per 1 ml of liquid will also increase the TH without making the juice taste like menthol. Sweet-Vapes is very popular and a good place to get juice. Only thing I can reccomend is spend the extra $$, and get a couple different configurations in the same flavor and see what you like best.