@astraleureka @TonyJWells @va3wft @ai6yr Agreed. Pretty much every Casio watch of that entire general time period was reliable, kept good time, and ran forever with just the original battery.
I never had to replace the battery in any of my own, so now I start to wonder. Could it be that it was more an issue of batteries eventually degrading and leaking than them running out that lead to replacements? I guess to some extent it could depend on alarm usage (if you used a bunch of alarms instead of once a day or something) but all in all they really lasted forever on those things...