I currently have the Vivoactive 4 and thinking to upgrade to 945
i run/hike 4 times per week and mountain bike/cross train sometimes
I love the body battery and stress metric
more interested in the features and extra metric the 945 offers with recovery time and all the small statistics, I currently use DWmaps to upload gpx trails for hiking hoping 945 can do it natively.
feel free to chime in.
i can still exchange the Vivoactive 4 for the 945