I can’t taste mixes with no nic. The taste is way to flat for me.I am guessing you could do it both ways, IDK. I mean folks test out odd mixes without nicotine but then the nicotine is going to change things if only slightly.
I would again (and I am guessing here, I tend to just use base if I am mixing it's easier) you might have more of a nicotine "taste" if your nic even has one IDK. I think you'd have to experiment because I really don't know.
I bet someone here will know, though.
Anna