When I first started vaping, since I was in airports a lot, I used to have a couple of XL 808d batteries that I'd use with an LR atty. When the eGo came out, it seemed to be the perfect fix, but the voltage just wasn't enough to do the job. I have, or have owned most devices, and typically use a mod at 5v or 6v. I just got the 1000 mAh Twist from Bruce yesterday (really just to see if it was worth it) and I gotta say, this thing cooks. I put on a 2 ohm HH atty and set it at about 4.4 V, vaped all day between that and one other mod without charging. Flying out today, and this will be with me for the trip. Keep in mind, it's not going to replace a Provari, nor is it supposed to. It is good at what it's supposed to do and for the $$, it can't be beat for form and function. Thanks Bruce.