For most people, the Apple Watch current gens don't have the battery life to last through a single full marathon (about 4-5 hours) with continuous GPS tracking.

For most people, the Apple Watch current gens don't have the battery life to last through a single full marathon (about 4-5 hours) with continuous GPS tracking. Meanwhile, even the cheapest Garmin has the battery life to survive a triathlon (10-12 hours of continuous GPS), and the highest-tier Garmins can handle several continuous days of GPS activity. That doesn't even take into account the fragility of Apple Watches. It's great that Apple provides such "generous" repair policies for these devices, since every single AW owner I know has had to have their AW watch repaired...multiple times...for trivial things. For "scratch proof" screens, the Apple Watches get scratched up more easily than any watch I've ever seen; and don't even try to drop them a few feet. A drop onto rock or concrete that wouldn't phase a Garmin or Polar will shatter an AW. And specifically to note with respect to ultras: at the Badwater Ultra (a 135 mile run in Death Valley in the summer), the temperatures got so hot that the AW watches worn by people acting as support crews for runners overheated and stopped working. Meanwhile, the watches worn by the athletes (mostly Garmins, but with some Polars and Suuntos in the mix) kept going strong.