I'm thinking of upgrading to the Istick 100w (currently using an Istick 30w with a Horizontech Arctic tank, 0.5 ohm coils) but not entirely sure. Anyone out there have one? What are your thoughts, any problems? I'm looking for better vapor production, I usually run at the max of 30w. I'm not too thrilled about removable batteries, but at least they can be charged in the device. Is there any mods available 75w+ with integrated batteries, at or near the price point of the Istick + batteries? Any advice is appreciated!