I’ve used the Garmin Fenix watches since 2016 (at the moment: fenix 5).
In my opinion it’s a very good way to monitor my fitness (especially when using the Tftna approach). I can set my HR ranges (i use a belt, cause the Wrist-based HR is not very accurate).
The Garmin watches are much more better than Suunto watches –> cause in my opinoin the Suunto app is not much user friendly.
You can count routes, climbing time, rest time with the mode “Climbing”. In multipitch routes it’s not possible to count it (to count one route, the watch measures the difference between starting and top, it counts 1 when reach starting point again, which is obvious not possible in multipitch routes). Maybe you can update a user mode (connectIQ).
I bought my watch used – it was like a new one…
I hope i helped you little bit.
All the best from Austria