My impression is the only difference between the two versions is the band and the bezel. I went with the cheaper version because I see no benefit to a little titanium.
I turn everything off when not needed except for the watch. If I'm just walking to the grocery store I'll turn heart rate off, count my steps, and put the GPS in UltraTrac mode. If I'm going on a hike I'll turn on heart rate, turn on steps, standard GPS mode. I plan on linking with my phone or computer only for uploading dives or uploading firmware and sync time/ date. Most of my personal activity data is of little historical interest to me. If I'm just hanging around I turn everything I can off and just use the clock with minimum illumination. I have no third party software loaded and don't plan to load any without a good reason and a little research.
Again, the Descent is new to me so I am a little fixated on its settings. This might not last. It has had little opportunity to clutter itself up with the bits and bytes of digital detritus that electronics acquire like a dog and fleas. Also, it has not been in the water yet, so I have no idea how dive activity will affect battery life.
If I were having battery life problems and it bothered me and have had third party apps loaded I would reset and clear the watch and avoid loading unnecessary outside software in the future.
As a data point, my dive log was empty on delivery, but I think the Chairman might be right.