I have some. The biggest pro is that the liquids taste better since there is no filler. Another pro is that I've refilled one cartomizer at least 5 or 6 times and it's still going strong. The biggest con is that they are messy to fill. The syringe (doesn't have a needle) works fine. But no matter what I do, liquid drips out the bottom of the little hose that attaches to the syringe. Also, even when I put a plastic .... plug in the bottom when filling, I always end up with excess liquid spilling out of the bottom afterward. As an fyi - I'm not overfilling them. I've been using about .9 mm.