I just got mine a couple hours ago and since no one else has mentioned this, I may have gotten a weird one. I tried it with an AW IMR button top and it didn't work well at all. I noticed the battery really rattled. I even turned in a ticket before I thought to try something. I have some small rare earth magnets that I got for playing with mods. I put one of those on the positive end. No rattle and it worked fine. I also have some Panasonic CGR18650CH flat tops. That worked a little better than the AW but, it still rattled and if I shook it, it lost contact and reset the
device. It worked fine with a magnet too. I'm not sure why I ran into this when no one else has.
As for the device itself. It looks good, I like the rubberized feel. I have my doubts about how it'll take it when I drop it in the driveway. Time will tell on that one.

I'm in the minority I know but, I prefer a knob rather than buttons and a meter. A knob doesn't reset when I change the batt and I don't need numbers to know what I like.

For the price though, it's a nice little device. It does what a VV is supposed to do and it fits nicely in a shirt pocket.
I haven't found the battery voltage display people are talking about. It's not mentioned in the instructions either.