I have had mine for a couple of weeks now. It's overall pretty nice, it was the first mod that I've had that I had to buy batteries/charger for, and I always said I wasn't going to buy anything that had an external battery because charging and carrying extra batteries seemed like a pain, but it's actually much more convenient than I thought it would be…better than waiting on my mod to charge!
It's pretty solid, I don't care that it doesn't have a display. I've been running a subtank nano on it, the SMOK sub ohm tank, and two RBAs, a mutation x v2 and a mutilator.
Just a few things about it that I'm not crazy about; it's really light, for one thing, which seems like it is a good thing but with a big tank it makes it really top heavy. Three days after I got it, it did a header off my workbench and my SMOK sub ohm tank became toast. With an RBA it's not a problem and the subtank nano is light enough that it isn't a problem, but if you wanted to use a bigger/heavier tank it might be annoying. The battery door is really really really tight to screw in, and it seems like those aluminum threads are really easy to cross-thread. I've had a few near disasters, and I can't help but wonder if they would eventually wear down and make the battery door loose.
Also, it seems to be fine with a tank at .5, but in my experience does not fire down to .4 like it claims. It will not read either of my RBAs if they are built less than .6. Not a big deal in the sense that I'm not really interested in super sub ohm building…but a little annoying for someone new to building coils to have something finicky like that. And while it is regulated, I have noticed something odd about it that is probably me just being a newbie but is sort of bothersome. Say I have my RDA on with a .6 coil, and the battery is fully charged…then I can crank it up to 40 watts and vape. But as the battery drops, I have to manually drop the watts or it misfires. So, once we're at like five little battery lights lit, it needs me to drop the wattage to 35 or it just blinks when you hit the fire button. As the battery life drops, the wattage has to be adjusted down to accommodate what the battery is able to put out. If you want to vape consistently a .6 coil on 40w, you are looking at swapping out batteries once the battery life drops down to five lighted dots, in my experience. Which is a pain for out and about, unless you're carrying a bunch of backup batteries, which isn't always practical for me personally. However, if you are using a tank, it seems to be able to fire consistently until the battery is to the shut off point.
Again, this is probably me being a newbie and not understanding how things work. It might not be an issue to anyone, or it might not be news to anyone who has been vaping for any length of time. It might also be that I have a janky unit…or that my habitual dropping and banging of equipment is to blame. Just thought I'd put it out there.
Overall, it was cheap and it works. It and a subtank nano will be my go-to setup when I have to go out all day and do something physical where a more fragile mod or a more expensive one isn't practical, and dripping isn't possible.