also wanted to throw this out there, there is a spare part, as joyetech calls it, called the evic easy head (don't laugh, thats what they decided to call it lol)
the description is kind of vague, but it has been assumed that it has the electronics of the regular evic, just no display and that adjustments are done through the computer interface, but it is dirt cheap, like $25.
i think this would be a perfect backup, or even regular use device, i rarely mess with my evic, once i have my coil / wick dialed in and even have found when i am out and about that the control ring will in inadvertently get bumped and mess up my settings.
the new head was just released this month though, so might take awhile to see it on vendors shelves (i have been looking daily)