I waited awhile for this review to make sure I gave it some time so I could maybe find flaws.
Anyway, on with the review.. All in all, I was pretty pleased with this device. (I’m using a 510 atomizer.) However, I’ll go over the negatives first. The biggest problem on this device is the switch. Mine worked fine for about a week, then I had to press harder and harder to get it to work. Eventually, I took it apart. Lost the spring right away (still haven’t found it). I replaced the spring with a pen spring, of course that doesn’t fix the issue I was having. At this point I didn’t really know how to fix it so I got my multimeter out and tried to figure out how to get it working again.
After awhile I figured out that it was the o-ring, wasn’t fat enough or something, because the washer wasn’t making contact with the 2 points in the switch. I did a little more reading on e-cigarette-forum.com to see if this issue was really wide spread. Apparently, it is. There were a few suggestions on how to fix it, the way that worked for me was taking some pliers and moving the contact points from the flat side to the round side.
About a week later, the button was doing the same crap again. The metal they’re using as contact points must be soft or something because it looked like one side flattened out. Did the same thing again, moving the contact point to a different round side. Result: fixed again.
What I’ve gained from this experience is that on the Prodigy V2 you don’t want to push too hard on the button, ever. That’s what causes it to get screwed up from what I can tell.
I’ve had no other issues with this device except for the fact I can’t stand using 3 – 3.7V anymore 
If they would fix the switch, I think this would be a really good device.
Vapor production is great, as you’d expect running 5V to a Joye 510 atomizer, been using it non stop since I got it. Very satisfying feeling compared to 3 – 3.7v. I go through about 2 sets of batteries per day, so about 7 hours per set.
My RYO cigarette tubes/tobacco hasn’t been touched for three and a half weeks. I intend to keep it that way.
Totals
Affordability – 9/10 – Well within range for most people to be able to pick one up.
Build quality – 5/10 – Problems with the switch, as I noted above. Otherwise, I’d say it’s pretty solid, but really the switch is pretty important so 5 points off.
Looks – 8/10 – Looks decent, especially with a silver atomizer and t-tip.
Usability – 8/10 – So long as the switch is working, it’s fine. Switch still doesn’t always work though, so 2 points have been taken off. Batteries last 7 hours per set (for me) so very good amount of time
Overall – 7.5/10 - Would still recommend to people *if* they don’t mind messing with the switch here and there or modding it with a fatter o-ring.
Right now I’m waiting on a GGTS, supposed to be very good build quality. Is $212 too much for something like this? Well the way I looked at it is if it lasts a long time who cares? The thing can handle almost any bat/atty combination so there won’t be any reason to buy different mods, unless it’s something unique like the juicebox (well, the GGTS actually has an auto feed system… ) or a double barrel silver bullet. Will write a review of the GGTS after I have about a month with it, same style as this one.
Not getting rid of the Prodigy V2 though, will be my back up device. The back up for that is the Janty eGo.
