I got a ProVari this year for Christmas. I also got the extension cap. I have always used iTaste products up to this point (VTR,MVP v1-2 x2 each) So I had a decent reference point. I decided to use the ProVari for a while before I gave my thoughts on it. I use a KayfunLite+ on it, and Panasonic 18650 batteries. Here are my thoughts.... I love this thing! It is absolutely great. My vaping experience with it has been enjoyable and consistant since the very first vape. I get almost 2 days of heavy vaping from a single battery. I would love to see a box mod version from them in the future. To be honest I couldn't be happier with the experience. Vape on!