based on how many people, 1 person had a issue, another person who did pm'd becuase they did filled it wrong. so not really seeing issues to be worrying about, these have been tested and they passed, there are many people we know personaly using these now, using many in rotation, no issues, same with bottom coil phoenix, im telling ya we have tested dozens, not having issues. definitly try to seal the black sleeve then retry.
I should of mention this though, the phoenix bottom coil is dry, becuase of this i would fill them all the way and then a tad more to wet the coil area, then pull back some juice to leave a air pocket.
doing this will alleviate getting a dry hit as you syphon the juice to the coil. this will wet the coil before hand avoiading nay issues or having to vape through 3 or 4 pulls until its soaked.