I just trimmed a bunch of notifications. My personal guess at the heaviest offender to battery life is dictation. I was doing a lot of texting on mine yesterday.
Wish i could say the same about the 38mm.
You forgot to add... Of course I had my phone plugged in to the CIG lighter because the navigation would have drained it rather quickly! The phone is doing the heavy lifting.
My question is more along the lines of how the battery performs after it's been charged over and over again for several months. Just like your iPhone, at some point the time a full charge lasts starts decreasing. How soon will this happen with the watch?