I've really enjoyed using my subox nano by kangertech but i am sensitive to oxidized nicotine and using the aerotank mini i have been able to avoid the harshness by using a no airflow setting (which the subox nano does not have). Problem is the aerotank's coils can't take much abuse in the way of chain vaping so i'm forced to use very high nic with that clearomizer, consequently not really enjoy a lengthy vape. I am looking for something along the lines of a kangertech subox nano but with the possibility to close off airflow to avoid oxidation. Any recommendations?