It is awesome seeing all the new love for the Tubo happening. This is an awesome vape that does more than just hold its own against any vape I have. Not tempted by the Dual much, the TubOG size is about as big as I would go on a portable. Swapping batteries is so quick with the magnetized door. About the only bummer was the Tubo not seating all the way on to my FC-188 without an additional adaptor. It hits glass about 3/16 too soon. I'm guessing it would sit the same on the FC-187, having the same size top.