However, because of the relative inaccuracy of these watches compared to the quartz, you will probably have to set the watch to the right time after 3 months of disuse. We owners of such watches will argue that it doesn't take much longer to set the watch than it does to adjust the quartz above for changes in time and date. Automatic watches can be used as above only if they are on winders. And 20 winders can be quite an outlay of cash you could use more pleasurably buying that Lange Saxonia. The reliability of mechanical watches is legendary.
Battery life is highly unpredictable.
My experience with batteries is that much depends on its age when you bought it and a variety of other factors, so you can rarely be absolutely sure when this temperamental power source will unpredictaly find itself shedding the last coulomb in its reservoir, leaving you timeless out there on the Continental Divide, where you plan to stay another week. Small wonder, then, that 'survival' watches are usually mechanical. Replacement parts for mechanical watches are widely available, including for watches dating back to the '40s and earlier. Also, they can always be made if they are no longer available, albeit at considerable cost. Not so with quartz watch needs, particularly batteries.