30 hours of battery life is a deal breaker. I don't want to charge my watch every day. I've been using the Garmin Forerunner for a few years now and the battery life is 2 weeks!
Daily charging for normal use isn't so much an issue once it becomes a habit, but battery life during extremely long (24+ hour) activities is pretty much a make-or-break feature for me. I've done some 50ks and while truthfully I may never do an ultra that requires that much battery life, choosing a device that can't almost feels like admitting defeat. It's kind of stupid but I know I'm not alone in that thought proce…
I went though a number of android wear smart watches ~10 years ago and had the same problem with all of them. I absolutely loved my Garmin 945M. I had it for years with hardly any battery degradation and it typically gave me 70-80% of the advertised battery life for many years until it was accidentally physically destroyed (caught the watch on a heavy backpack I was taking off, which ripped off the watch pin anchor from the case).
The Fenix 6 I have now is not nearly so good. It advertises 2 weeks of battery and I'm at 53% after only 4 days or so. I blame this partially on their crappy iOS support where you cannot filter apps out, so every #$%#$%^ slack message I get buzzes my watch. I had a Pixel phone when I had the 945, where you can filter out garbage notifications. This is really Garmin's fault, since apparently Coros and Pebble can filter notifications on iOS. I'll switch to one of those when this Garmin dies unless they fix their iOS support.