I have had my EVOD for a few weeks, and have really gone through some coils. 2.5 ohm heads at 4.2 volts. 60pg 40vg juice. Like everything about it except for the occasional, no warning burnt taste that everyone talks about. Sometimes I can get the flavor back, sometimes the head just needs to be replaced. Judging from the posts I've read, it just seems like something you just have to be ready for and deal with. I can put the EVOD on my ego-c pass-thru, and don't get that taste. This weekend, I picked up a new T3S. I figured it would be more of the same, but wanted the extra tank capacity. And ordered supplies for rebuilds. Well, I have had it three days now and haven't had that taste once. It performs Grrrreat in my opnion and keep waiting for that had hit that hasn't come thus far. I don't get it. Basically the same unit with more capacity. The only difference is that center pin on the head. I have noticed the hole in the EVOD pin is smaller in diameter, and I assume is the reason for the tighter, less airy draw. I am wondering if the wick just isn't sucking up enough juice quick enough for the hotter burn due to more restriction on that center pin/tube.