Head function and personal experience seems to be more of a direct result of User interface than QC issues.
Bottom Coils have the advantage hands down in functionality as they are by design submersible. Top coils completely Flood if tipped to long.
It would be near impossible for one person to receive All POOR QC heads and another to only receive GOOD QC Heads.
For those unable to find proper function it BCC units, Top coils may be their only solution. Sadly there are those that never get satisfactory function from a top coil unit.
After using some Brand/form of almost all delivery types, I can confirm (
in my opinion) Only the Nano Clearomizers have serious QC issues as a specific design. After testing 10 units I found 3 to work excellent, 6 total to work acceptably, 3 kept getting dry hits no matter how much priming was done and 1 literally had no air flow, even off a device.
Even this was most likely due to the small design and limited space in which to place a hidden Bottom coil and wick.
Generally QC issues are Manufacturer specific.
Defective product will get through any production. The % is a direct reflection of QC measures taken.
Batches are normally sampled and only a number of items within the batch. The manufacturer that samples higher numbers of batches and samples in a given period and acts to take corrective measures gains the most trust and consumer support.
Unfortunately NONE of these manufacturers can make the Human interface function properly. This task is up to each individual.
Now, each of us must explore and find things in life that work for us. No need to keep saying (X) is total garbage if someone else is loving their experience. This can only be quantified by (
IMHO) and is simply a personal Rant.(which we all need from time to time)
Here is to hoping everyone finds their sweet Device and succeeds!
Vape on and enjoy