I honestly don't know how you would be able to tell new from old stock. The boxes don't have any kind of lot number or date of manufacture on them that I can remember to be able to identify a specific lot of cartos. Maybe a vendor could tell by purchase date, but I'd be very leery. The last ones I got came loose in a large ZipLoc bag. That's really bulk.....lol. Looks like SmokTek has shot themselves in the foot and needs to stop the bleeding.
The last two I tried before giving up sat overnight after filling them. They were used in a tank, so I don't see how after sitting for over 12 hours, immersed in juice, they could not have been saturated. That is why I'm convinced there is something wrong or changed with the polyfill. They burned up in less than two days. I know the cartos are considered to be disposable, but two days just doesn't cut it for me. I got tired of having to drain tanks and replace the carto so frequently.
What really frosts me is after notifying the vendor of the situation, nothing was done. Of course, I was the only person who had reported a problem -- think I mentioned that in a prior post, sorry about my dain bramage. I understand about the DOA business, but this is a situation that obviously was serious beyond a couple of DOA cartos and needed immediate attention. To let the customer end up holding the bag left a bad taste in my mouth. I'm just glad Boge came out with the longer carto and I'm done with the vendor and SmokTek. I am not rich enough to keep taking the chance with these cartos. I would need very definitive proof and a sign from the vendor they were willing to "share the pain" in this case. It truly is a shame for the industry as a whole when something like this happens.
You used CCV? 
I think I've got some pretty mad Vendors at me right about now.
