I bought the Smok Alien.. It has become my new favorite mod. It is small and very well built.. Just feel so solid in the hand. The fire button is so nice.. When comparing it to the smok ultra or smok h-priv it is def the best of the three. It doesn't move or rattle like the other devices. It is just solid. Be warned though Mike Vapes received three smok aliens and two of them had strange clicking sounds on their fire buttons so there is def a quality control problem there but luckily my fire button doesn't have any of those issues it is just really nice to use. The screen is well informed and just looks like a nice quality screen. Very sharp and well defined lines. Feels like a quality OLED screen to me but I have no idea what kind of screen it is. It also just looks so much nicer in real life. I feel the pictures make it look like cheap plastic but it is anything but cheap looking in real life. One thing I do not like about though and this is just nitpicking and isn't by any means a deal breaker is it kinda a lefty device.. If holding it in your right hand your palm is over the screen. I feel it is best used in the right hand by using it to thumb fire this way the screen faces out. Prior to getting this I was using the ipv6x and let me tell you it is just so much nicer. While I love the ipv6x it has given me some problems. These problems are quality control. I probably just got a bad one. First the ipv6x 510 pin is slightly positioned wrong and my tanks are dipping to the right a little when looking at the screen. Also the battery door opens on it own if you are two rough with it.. Like for instance if I put the ipv6x down too hard the door pops open and falls over with the batteries popping out. So you have to be somewhat gentle with it. So my point being the smok alien just feels more solid and better put together then the ipv6x. The smok alien is shorter then the ipv6x but it is significantly fatter. Even being fatter it fits really nice in the hand and the smok aliens fire button makes it so you don't have to search for the fire button or extend your index finger to fire which is really nice. The chip it is using I believe is the same as the h-prive with a different screen. and if you ever own a h-priv you know they just work and work very well.. In both watts and temp control. So if you are interested in performance go check out a video on the h-prive or xcube ultra. im sure djlsb will have a perforce review on it in the near future. All in all I am very happy with this device it is the perfect on the go device for using tanks at over 75 watts.. the dual battery setup makes it so you don't start having power issues when the batteries start to get low. If you are looking for a on the go dual 18650 I would recommend this device but if you want smaller then the ipv6x is still a smaller device and fits in pocket a little better. Even know I had a small rant about the ipv6x I still love it for it still performs great and a very nice form factor. Anyway I thought i would share my experience on this device for i have fallen in love with it.. But only time will tell how well it holds up but I feel it will hold up just fine.