Found very quickly that 18mg for me was too strong - and with some juices it even made my oesophagus cramp up - almost stunned it if you will - dropped down to 12-14mg and no issues.. Will be dropping mine again in future as well - however the missus can go up to 18mg with no problems but gets similar effect at 20mg plus as I do at 18..
We think however this is the true "throat" hit that some smokers crave that we are experiencing - we have never been strong baccy smokers - being on ultra thin rollies before we quit for vaping and hardly smoking all of them either and never really taking a huge drag back..
Be interesting to see if others experience the same osophageal symptoms as us on the stronger NIC's