That one doesn't appear to have a glass window...I don't have any idea how to tell how low the juice is without some sort of window! ack! Do they sell windows separate?Have a couple of 3.1 in my collection. But at this stage of the "evolution" of the KF, I think that's a bit high...
They're heavier than the other models, but a good tank for MTL. And since you say you like tighter draws, should be fine. But vaporrange still has some of the V2+ for $10, with dual air intakes for more adjustability. And lighter.

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