OK, fine. Again, that's not what I was testing. Not 'cheap e-cig pens' but that specific (magic) function in some of them that let him happily vape at 4.2 Volts while the rest of us were stuck with less. I think I tested that part, what I set out to do. It is not, at that level, a superior unit.
I do not believe I 'tested the wrong one', in fact the one you suggest (while also interesting) would not have been productive to my needs.
OF
There seems to be still some confusion here. We've been discussing three different cheap Chinese batteries with THREE DIFFERENT notions of "variable voltage" and TWO DIFFERENT "color change" "variable voltage" features - One is regulated to 3 levels, one is unregulated and the third is boost-buck "truely" variable.
OF tested one of the older common 3 level "VV" eGo clones - It changes the color of an LED ring from red (3.2v), red+blue(3.7v) and blue (4.2v). It absolutely does NOT boost the voltage of the single Lithium cell inside of itself, but rather just changes the regulation circuit to three different references (and this does give about 3.6v delivered to ecig user who are likely used to 3.3v on regulated eGo battery sticks).
The OP stated he was using an eGo-C Joyetech battery. The manual for these states that the two modes, which color change between white and orange leds, are regulated (like older Joyetech devices) to 3.3v under load and what Joyetech states is "variable voltage", but is simply unregulated. This second mode does NOT allow 4.2v, on demand, but does provide _exactly_ the same improvement a V2.5 or HVD head does on an Omicron V2 - no more and no less. (Joyetech "explains" the second modes is "variable voltage" because the voltage will vary over the battery charge, unlike their regulated 3.3v mode.)
The third battery is the Joyetech twist. This is a real cheap Chinese VV ecig which can blow clouds with Omi carts easily. Other people have posted more than enough on this one.
-NDA