This watch replaces my Fenix 3HR which I've worn for a number of years, but was getting a bit tired. (losing accuracy w/ distance as well as elevation) I was also looking for more of the current features out now, ie built in HRV, Body Battery, Sleep, Pulse OX etc. I wear it day/night for everything except out on the bike, where I use my Garmin head unit. The only exception is if I don't want to wear my chest HRM, I'll wear the Fenix to get my HR. I'll also wear it on the trainer occasionally for the same reason.
The accuracy of the watch on trail runs is excellent. I've been happy with the mapping and navigation.
I think my biggest take would be for people coming from an older Fenix series. The 7, is very intuitive. It was a seamless transition. No need to re-learn an entirely new system. And with that, the 7, is better in every single way. Giving me much improved accuracy, as well as all the current fitness metrics. Even with the many new features over my previous Fenix, the 7, does not feel "overwhelming" in added complexity. I thought there may be a big learning curve to adapt to all of the added features. But that has not been the case. Again, very intuitive and well laid out for those coming from a previous Fenix. The GPS is much better than my Fenix 3HR. I use it weekly on forested trail runs, with no issues.
There is absolutely nothing I can think of that I would change on the Fenix 7.
I've owned a Fenix 3, a Fenix 5 and now the Fenix 7. The product continues to get progressively better. And the. battery life on this one is unbelievable. And I haven't even had the chance to increase the battery life with the solar capabilities of the watch. This is a must have for anybody who loves to track their training, health related items, set targets, etc, etc. I would recommend it to anybody who wants to have the best.