Assembled the new battery pack, and took the watch to the desert. It's a CA/NV type of desert, think DV or Mojave.

It's important to test in different conditions, such as high temperature, and high UV light. Also, climbing and hiking in a fairly extreme environment subjects the watch to stress and vibrations, as well as dust, dirt, sand, and shocks, which are important use cases.

So far, so good. Pictures attached.