If you abuse any ecig, battery, mechical, digital, custom made, whatever what can you expect other then a very short life span! So far I give away a Vamo V2 I bought last January to someone in need of one in spotless condition with the gold replacement contact put in last year still in prime condition. One battery thought to have bit the dust proved to be shorted a little by some leakage of ejuice last summer and still works like brand new now.
Another battery that was in my pocket a few times each time with a 1.6ml clearomizer attached saw side pressure against that and the connector popped out of the end. The second the two wires came off!

I gave that to someone who works in electronic assembly once I was able to determine where the wires broke off from since those wires are too fine and need someone with similar experience with fine wires as far as microsoldering, etc.
Now I was definitely taking a look at the V5 as I was mentioning before but went with other variable voltage/wattage mods here's a fast look at the latest in use here. First the Groove II placed up nest to the MVP2.0 when someone was asking what would be a better place to see the button on the MVP2.0 without the shoulder surrounding the button itself which makes it awkward.
Then what I found does the same job the Vamo V5 would do only lighter in weight is the SMOK ACE VV/VW 18650 or with SID battery tube(bought separately) the 18350 size battery power telescoping mod. I had find the second one in gold to have a matching pair of course!
I had an accident with one of the Itaste VV V3s where my hand must have had some ejiuce on it and the battery went sailing to see the tank on it ruined as for the plastic tip molded into the tank part as a one piece constuction while the battery is still good as new. A close one however. Yet with each of these batteries and mode people tell me they have had numerous problems while I find them reliable! Something isn't right with that when this happens to everything they get!