Very good, comfortable to use & fits well in the hand. Bottle is easy to get in/out, just remember to unscrew the top when refilling to avoid a puddle of juice (definitely haven't made that mistake ). Menu system is easy enough. Only downside is 25mm + atties will overhang & not a pocket mod as it packs some weight. TC I haven't played with as got a Drone for that.
My latest toy. Tiny, but fits a 22mm perfectly. No wasted space, no noticeable voltage drop, engraved, so nigh on perfect. Ok, only takes the smaller bottles, but not a problem with a refill kit, and due to the very short throw, the locking ring needs trimming down a touch.
Already moved into my top 4 mods list. In no particular order, they are the Runt Mini, Phobia, Calibre Concepts X2, and this.