To preface, I'm generally quite happy with my purchase. Shipping was fast, communication was excellent, and the look, feel, and wearability of the watch are remarkable at this price point. My only issue is that the watch was missing its case gasket—the all-important rubber o-ring that sits in the channel in the case beneath the edge of the screw-down crystal and ensures the professed water resistance of the watch.
Yeah, that's a problem.
I had worn the watch on vacation while swimming (read: leisurely floating in a pool) with no apparent issues, but later in the evening I noticed fog under the crystal—clear evidence of a leak. The watch continued to run, keeping good time at that, but the lingering humidity persisted for the remainder of my trip (during which I made certain to keep the watch well away from water).
Upon returning home, I removed the bezel and disassembled the case to dry things out and survey the damage, at which point I discovered that the aforementioned gasket was simply not there—just an empty groove where it should have been.
Again, this is a solidly built watch, and I'm assuming that this problem is an aberration, but it must be said that more attention needs to be paid during assembly, and caveat emptor to anyone taking the professed water resistance as a given.