Can anyone educate me on how well refilling prefills works?
Yes, I believe most of us here could.
If the flavors don't match but they mix well does the performance hold up?
That depends on dry the you let the pre-filled carto get before you add more fluid. Usually it will work just fine. Back when I was doing this, I got anywhere from 3-7 refills out of a pre-filled carto.
And if the pre-fill is completely flavorless can I rescue it with some new liquid?
Generally speaking yes. At the very least it's worth a few drops of ejuice to try!
Hope that helps!
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