I have been vaping awhile now and I know the unknown is vaping flavorings especially custards with the 3 bad chems ..truth be told i no longer buy vendor made juices due to the high flavoring and unknown ingredients additives used..flavorings were not meant to be inhaled even natural flavorings can be bad for lung tissue..thus resulting me to diy unflavored high vg mix and it's actually quite nice so I can mix up a good flavor for that couples times a day when something tasty is a plus..I figured why I can't settle on an ADV and it's because most any one flavor will get old some faster than others and I found vaping unflavored 80% of the time keeps less flavoring chemicals in my lungs and makes those flavors I enjoy even better when I do vape them..diy is the cheapest and best way to vape IMHO and this is coming from someone vaping for two years and been through many many high end juices..yes I like those flavors..yes I like the nice bottles and marketing..but why vape expensive flavors all the time I don't know what's in them I like having control over what's in my juice and I found I can mix juice just as good if not better than some high end juices...(by the way custard lovers the new capellas vanilla custard v2 which has no acetoine diacetyl or acetyl propionyl is very good)..I'm not convincing any one to follow what I do I just feel safer vaping unflavored most of the time until the unknowns are figured out..I never thought I would go the unflavored route but it's such a nice change of pace and very cost effective you could even mix a low percent flavor if you dont like the neutral taste to give you a little flavor..just some food for thought would like some opinions and feedback..after all we're in for the nic right..by the way if you diy check out bullcityvapor they are fantastic got my order to me in less than 24 hours regular shipping got shipped notification within an hour of placing order with tracking