Here is my experience so far (found your forum yesterday but could not post until today)
I bought the Titanium - Black Dial - Black rubber in Mayors here in Miami, but had to return my first watch as the side button did not work
Second watch is fine but have had all kinds of experience with the battery:
* When I first got it we connected it at the store just to make sure everything was working OK, so the battery just charged for a little bit )probably no the best first charge in retrospect) anyways I also skipped several setup steps just to test it and ended up restarting (un-paring) the watch since it was not receiving notifications .
After that charged it overnight and the battery lasted for about 10 hours with medium usage (I did have a third party face on it, Pujie Black), when checking statistics the process "Android System or Kernel" was accounting for 45% of battery drain.
I was of course not satisfied with the battery life and found the forum talking about this, at the same time I received the update and installed it right away to test, but after update battery got even worst (it only lasted for like 8 hours) with no apparent usage but screen 1%
So I let the watch run down to 0, did a total reset from the Android reset Menu and let it charge for the night
I have not installed any apps and left it with the simple 3 hand dial and have been using it for 2 days straight now without charging (all antenas On and light use of the watch, just to check notifications from calendar and a couple of apps like life360.
I did turn airplane and theater mode last night before going to sleep, and turned everything on this morning again, but now I know the battery will last under this scenario for about 2 days straight without charging (about 36 hours to be more precise)
I will let it run down to cero again tonight and charge overnight and will play with a couple of apps install my watch face with Pujie to see what effect that has on the battery
Btw. watch only charged to 97% as others have pointed out.