As a beside I might be different because I'm not using 28g kanthal in my builds.. with the kayfun 4, I found the best flavor using 24g. Kanthal at about 1.3 - 1.4 ohms..(with organic Japanese cotton for my wicking)
Which might explain the sweet spot for me being a little bit higher a voltage, don't know, but this is where I'm getting the perfect vape, for me.. at least in the kayfun 4..
Just started working on the Taifun gt3 ... that may or may not end up different.. lol.. I keep flooding it so far, so I don't know how it's going to end up!