I wore a G-Shock Wavecepter while serving in the U.S. Marine Corps. I recall that on both of my shipboard deployments (2004 and 2006) I was very excited to have my watch set time automatically. It indicated that I was finally nearing the U.S. East Coast. It helped to be an aircraft mechanic on night crew, as I was usually on the flight deck when it tried to set time.
Have solar atomic version. Don't wear it much these days. Mostly when I travel. Been on my dresser 2 years collecting dust but gets some sun. Picked it up the other day for a camping trip. It was both charged and had the correct date and time.
My battery has given up the ghost, and it's probably in a box of stuff around here. At the time, putting a new rechargable in it was impossible. I wonder if that's changed now...
Edit: Neglected to mention mine was also solar
There are anecdotal reports of solar Casios going 20+ years on that battery. Which makes sense given that its capacity should just gradually reduce over time - and when you start with full capacity that can drive the watch for over a year (assuming no backlight etc), even if it drops to half that, it's still very much usable.
The newer ones go into sleep mode until they sense some movement. Each morning when I pick up my GW-M5610U-1 (of course with the titanium mod), the display is blank and then fills with data within a second or so. I really like the feeling that although I hopefully have a few more decades to live, this watch may be my trusted companion for the rest of my life.
