First let me add a little balance here. I have had two go-go kits and have been using all the batteries and 11 V1 (black blank "sticker" type) cartos all being topped off on average every other day. I screw every carto down on the battery until it seats completely. In my experience the draw is way to "loose" if I don't. While I did have to file down the charger connector on both chargers and one charger doesn't light up (it still charges fine), that's the most problems I've had. I do feel for the ones that have had problems and I believe these are serious and need to be addressed by the suppliers.
I worked as a mechanical engineer for 10+ years and I understand the design and why it's the way it is. The center posts have to be insulated from the outside ring. So you have a couple choices, you could use a solid type of insulator (glass or ceramic type of material) and then try to come up with a way to allow for manufacturing tolerance variances or you can kill to birds with one stone and use a flexible insulator. The flexible insulator allows for the center posts on both the battery and the carto to compress slightly making sure you have a good connection between the two. It also makes manufacturing/assembly easier as well as providing the needed insulating quality.
We're talking about tolerances in the thousandths or even ten-thousandths of an inch. Early in the thread we were talking about this and I measured a few cartos and all the batteries to see how much they varied. In my case they were all within two thousandths of an inch. Then I measured how much the center post would compress while coming back up to the same spot when the force was removed. In all cases, they would compress nearly ten thousandths of an inch. I can see some eyes glazing over so I'll sum it up....
I think the design is sound. The insulator is most likely a silicone rubber type of material which would give it all the properties needed, heat resistance, chemical (juice) resistance, elasticity, and dielectric strength (the insulating property).
I think the real problem here is quality control at the factory during manufacturing. Just like an engineer huh? We blame these problems on manufacturing and the guys in the factory blame it on bad design.

But.... from what I've seen with my limited experience, these things are designed well. There's always going to be bad electronics (buttons, solder joints, components, etc.) and there are always going to be manufacturing variances. Are these problems more prevalent with e-cigs? I think so. I also believe that with any new design there are going to be some changes to make things better. That's one of the biggest problems with being an "early adopter" of any new design. I also chose Beta over VHS for three times the price way back when.
To sum up... if you were brave enough to stick this one out

I'm sure the suppliers will take care of the problems, remember your problem *is* their problem. Also remember that there are quite a few of these things out there now and a lot of the people using them are doing just that, vaping the heads off and not posting here every day saying the same old thing.... "Still working just great".
I have not dealt with Drew but I do know that Frank has a bit of a problem getting back to you with email. Not the way I'd personally do business, but I can say that he has always gotten back to me eventually and made things right. I would just send another email every couple days to make sure you don't get lost in the shuffle. Again, I hate to hear of the problems some are having and I sincerely hope you get squared away quickly. But I believe those having serious problems are in the minority and am very hopeful that they get a good set so they will know how good this PV can be.
Take care Go-Go Nation!