I should've mentioned that I did get one a couple of months ago and at first I couldn't take it out of the house because of the battery issue. Well, I was still doing DC tanks and you know how they eat batts. I just got into Kangers recently and I think they go hand in hand with the Robust. I'm usually at 3.2 volts or even less sometimes. I don't leave home without it. I do carry 4 batts with me for backups (obviously), but I only use up one battery while at work (give or take a couple of hours) but I don't usually chain vape at work much. I have to have something small especially for work or else it just gets in the way. This thing fits in my pocket nicely. I may even get another, but I would want a Stainless and can't find one as cheap as I got this one. Anyhow, I think they're a little under rated, now that I found a head that works good with them.
Oh! And yes, I've seen a lot of reviews on them, including the Grimm Green and Phil Busardo reviews.