I bought cartomizers from heavengifts.
For me the experience is different. When the carto starts to taste burn I just fefill them, but then after 3 or 4 refills the problem is not burning taste but low vapor instead and after the vapor production drops there is nothing that I can do (still) to bring them back.
When I took apart the first carto it did had a hole on the fiber where the coil is but the fiber didn't have that brown/black burning look, it's just white with a hole.
The thing that I can't understand is that the carto still reads the same resistance as when new, so the problem is not at the coil itself like when a regular atty dies, the problem is that little hole on the fiber. So my logic says that is really a wicking problem. The solution seems simple, just reacomodate the fiber so the hole moves away from the coil, but I haven't been able to succed cause the fiber is too tight in there