Iv been using the 510 for a few months now, I really like it however I notice that after a few days I loose the throat hit. I use 24 mg juice. I go get a brand new atty ( I have several brand new ones stashed) and boom the throat hit is back in full force. I clean the old attys with alcahol and distilled water, let them dry completely, sometimes the vapor production is better but they are never quite as good as a brand new one, they still work but not great, Any one else notice this?