For me it has to be the KangerTech Protank Mini II purely because my Itaste VV VV.3 hated the thing. the Itaste really struggles to read the tank, to be fair to it, when it paired with the Itaste it vaped a treat, but its too small, 1.5ml capacity? no thankyou. Anyway I had the Protank Mini for a week before it started leaking and i ended up with a mouthful of Eliquid. Other people may love this tank, for me its a big no no after my experience.