I stopped using percentages. I just mix down to 12mg and then I add drops. I do not care how many percent a vendor says
For
tobacco's I'll start of with 2
If a company sells mostly super concentrated percentages can be a pain to work with. So i'll go with drops. I'll start with 2 shake, test, not enough, 2 more, shake test repeat
Tobacco's generally need a bit steeping time to test flavor. So I just make 3 bottles of 5mg with VG/PG mix and no nicotine
I'll add 2 drops in 1 bottle, 4 drops, 6 drops in a bottle, let it sit for a week and test
For myself I found drops working out alot better then having exact percentages. I bought alot of stuff like gradual cylinders etc. I do always write down how much drops goes in what. Some people might like stronger, some less. But having not enough of flavor from the start is better then having it overdone
So always start of very low, give it a try and repeat. If you are close to the flavor and you think, it might be better with a drop or 2, stop, let it sit for a day or 2-3. Try again. Some flavors are also more potent then others