No issues here. Always got my stuff and they never sent the the wrong thing. I recommend manual
batteries for all slim ecigs - harder to damage or kill with
juice leaks and easier to get a good hit. I like the long 10-13 second cutoff.
Always check if your carto could use some
juice before switching to a new battery. These are real 3.7v batteries and are hotter fresh off the charger (like 3.9-4.2v instead of 3.7v). And if you bought a kit - the combination of their juices and ther WOW cartos and batteries can pack quite a TH punch. Some 24mg vapers find they need to drop to 18mg on this model etc. I use two of their WOW juices as my everyday juices, plus a couple of other juices that are thin and clear (PG w/ 20% or less VG). And I recommend you also try the cartomizers from SmokelessImage or Bloogplanet which are a bit different and nice bottom coil cartos.
I use a plastic or delrin drip tip as a mouthpiece instead of the end cap. especially on V4L WOW cartos which can get pretty hot on the lips.