I have 3or 4 of the t3 tanks, I love em, haven't had one leak other than when I flip it to fill ill get a few drops in the bottom of my drip tip. They also sell assorted replacement heads for them in a few different resistances. Haven't gotten any of the replacement heads but I have rewound a few (similar to rewiring a nova) I usually sit about 1.4-1.8 ohms with cotton wicks.