Fénix 6 user here, solar if it matters. Pairs with iPhone nicely, does notifications and can be used for music via a number of systems, but perhaps a little more convoluted for that than Apple Watch.
Plus side, battery is at 7-10 days even with HR and O2 monitoring on constantly. Works great for tracking routes, especially MTB where you may not want an out front mount.
I will admit that Garmin Connect is very difficult to use in real terms, the app is better than the website, but crap for route planning. Explore is much better, but not intuitive as to how you get routes from the app onto the device. Once you work it out it’s fine though.