I've been really pleased with my eVod tanks, been one of my most reliable performers so far. I have a few of them and use them regularly on the go.
My only suggestion, coming from someone who wished he'd received this advice, is to definitely consider VV (variable voltage) batteries instead as your starter kit. It allows you to dial in the voltage a bit to customize the experience for different juices. You'll find some do well lower, and others higher...but it's nice to change it up. As for the heads, the eVod's are great...but also consider the Kanger Mini Pro-Tanks. They're a little bit more money, but they can handle any kind of
juice, are a little bit "better" than the eVod's and should last a fair bit longer. It's not too much more to get into these items and it's where I wished I had started...but then again, I didn't know that until I tried them.
A coil will last somewhere between failing right out of the package, to a day to a week or two, depending on a lot. Failure aside, my average is around a week or so. Darker/thicker juices will last less time. In the vein of the hobby aspect, I rebuild my coils, so they're fairly cheap to maintain...and I'd rather get great flavor, so I probably replace on a little more cautious schedule than I used to. You might get more, or less, but definitely get extras!
Some tropical flavors can crack that tank, you'd have to check with the supplier to be sure. (They may not know, either!) Thus why I think it's wise to look at the mini-pro's instead. You just won't have to worry.
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