I have a few USB Passhru batts from thesmokesafe.com and havent had any problems on two or 4 hole atomizers, my friend that bought one did have a problem, it definately wasnt the passthrough, i put a piece of plastigauge in there (engine builder stuff to measure clearances) and its the center contact not making contact, Now to me, if the usb batt is working on 90% of the atomizers... it seems more to me that it is an atomizer manufacture defect,well not a defect if it works with batteries, but the center part... which is surounded by rubber on both the atomizer and the battery... that rubber piece could just be a fraction different thickness and make no contact.. does that make sense?? i guess it could be the battery too with the rubber piece, but if it works on some atomizers and not others.. i guess its just hit and miss like you guys have said... I wouldnt say it definately thesmokesafe's usb battery or so and so's atomizer.. we're mixin parts here.. some time there is bound to be some incompatibility. But if you have issues James will for sure help ya out.
Cheers to all!
Jason