Well I've got a 901, classic pen, Kissbox classic and a screwdriver. I'm going to to a fuller comparison but what I will say is the screwdriver outvapes them all. The Janty comes close with a fresh battery, but the screwdriver is way ahead of them all.
I have no axe to grind here. I bought and paid for them myself. Trog may be a cantankerous old git, but he makes an e-cig that outdoes everything else I've tried. (That also includes a Bling but that tasted like cigars so I was biased against it)