Okay. I'll bite here.
I'll call in to question the equivocation.
Albeit, there will always be some issues with manufacturing, the single largest variable is user behavior. That applies to any device. Not just vapes.
I've used quite a few of these units, and taught number of friends how to use them and everyone has a different set of techniques (it's not just air intake as you suggest, but things like packing, grinding, quality of product, etc). Heck, I was "Mr. Grind'n'tear-was-good-enough-for-granpappy-so-good-enough-for-me" and I saw a performance increase when I finally gave into to grinding.
Or look at the fact that dreamerr, OF, and myself have all used the same exact unit with a variety of results. (none of us were in the same room, so we couldn't "instruct one another.") The human variable is always a big one.
Are there still a few units that have issues? Looks like it. But I think you seriously underestimate the impact user variability can have.
Agreed. Of course the first 4 things you mention are all basically the same issue. (The last one I addressed in the previous sentence.)
DV has some solutions for the first four things. In the mean time, I am really liking the glass flower solution. The efficiency is vastly improved.
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