TFV4
Pros: Versatility, Easily Rebuilt RBA decks, and some crazy power.
Cons: Premade coils suck the juice , poor QA, cost of coils and the swing to fill can get knocked open in your pocket.
That would be my simplified review.
I'm absolutely loving the tank, dual RBA is a solid setup for me, 50-90w vape on the coil setups I've come up with. Works beautifully. Want a lighter vape you can make your single RBA into a 1ohm+ setup, my thought was for "on the go" vaping where you don't want to be blowing plumes. Likewise I can grab the quad coil crank it to 120w and finish a full tank of juice in less than half an hour all the while being a mildly warm but anything but harsh hit.
I did have a full tank leak in my pocket the other day because that swing thing came open, easy fix though, they include vape bands, just have on on that part, slide it down or off when you want to refill then put it back. That's only a concern if you walk around with it in a deep pocket with a bunch of other stuff that can knock it around. Happened once after a week of doing that, so not really a huge concern but worth mentioning I thought. Also personally I was lucky I guess as I had no factory defects, but a lot have been reported. And then for the juice concern, like I said the quad coils you can kill a tank in under half an hour, not necessarily a bad thing, but again something to be aware of. Though with the high wattage usage it also sucks the juice out of your batteries, more of a concern there. Finally the cost of the coils is an issue, however the fact that the RBAs are so solid I think that cuts into that quite a bit. When I want to I can pop in a premade powerful coil, when I'm just relaxing at home and want something to vape I can use my dual RBA which is solid enough.