I have juices from two separate vendors (who I will not identify). One is very well known and a bit more expensive, the other a bit less well known and inexpensive. What I've noticed is this: juice from the more expensive vendor seems to last longer. Has anyone else noticed differences in not just the taste of the juice, but the quality and vaping life of their juices, where 20 drops from one vendor lasts longer than 20 drops from another? This observation is completely unscientific, BTW.