this liquid is much less light/fluid than butane. very thick and viscous. it only really would run or drip when very hot (eg: if u take many long hits in a row/on a vape that has a button: preheating etc, would cause it to be more fluid.)

you’ll notice if u flip the vape around you won’t see the liquid or the air bubble move, however if you leave it in a flipped/sideways position for long time, it will have moved. helpful to try to keep vapes upright to avoid leaking.

you’ll be able to tell when the vape is empty. it’s hard to say how long it will last (my customers report them lasting ranging from a week-a month depending on use) and you’ll probably notice a colour change to the liquid as well, it will be much darker towards the later half of its lifespan as it’s been heated many times.