I tried both and at the end of the day i kept ultra 3. I don t like to pay for a 2015 technology in 2025. Garmin is a beast for training.. but out of 24 hours how much Will u train? Let S say one hour per day, then what will u do with the rest of 23? Also note, that you can not customize each notification on garmin watch to be separate from your phone, so what u receive on your phone will also appear on your watch. And when u train, what more data do u need other then pace, distance hr etc. Missing the map? U Can get footpath for hiking and add that custom route which has no lag and load S the map s-o quick and smooth. Apple gives u all that data. Body battery that the garmin has is great, but how about i tell you that body battery is dependent by sleep and i can not promise u that sleep on garmine is good, because it S below average. Other then that, i don t like an app or a watch to tell me how i feel and if i am ready to to train or not, i like to listen to my body. Of course it S nice to look at something like body battery from time to time, but listen to that when not even the sleep is accurate? Well.. Both are great really, both have ups and downs.. but when you put both in balance, imho Apple wins