Instinct 2X Series

My fully charged Instinct, after a 5 hour hike, would go from 28 days to 24 days of battery left. My Venu3 would go from 100% to 75%, so no, I would be fine without a charger over the weekend. Your AWU wouldn't be.

if he is working a lot in the rain, get him something with more than 2 buttons so he would be able to use the watch using only the buttons (without the touchsreen) if he needs to, something like a forerunner, or instinct (doesnt have a touch screen) or a fenix (but a fenix is one of the more expensive ones)

I found my perfect smart watch in Garmin Instinct 2, since it’s like a G-Shock, but still has the features of a smartwatch like notifications, alarm clock and workout tracker. And the best for me, I just have to charge it once per month.

Instinct 2X solar. Picked it for the battery life, solar charging, and flashlight. Don’t love the size but it was the best option with those features that fit the budget.

All true except advanced metrics. They are also present in Fenix (it has even more features for hiking) and Instinct. Forerunner is not more advanced. The rugedness is mostly about the bezel. In fenix and instinct it has a rim which gives extra protection to the screen. But that means rugged watches are more bulky what can be a problem in the gym. The real question is lightness of forerunner vs battery life of fenix /instinct

Instinct 2/3 are probably the best bang for Buck when it comes to solid long lasting hiking watches.

Garmins might do better for you then. They are great at tracking and have smart features but also get a week or more on a charge. I love my instict 2 for how simple and non intrusive it is.