@miha188
Take the one you like most and that suits you better, because it's all approximately the same. Some Garmin fanboy will praise Garmin, Suunto fanboy Suunto.
I, for example, have a Garmin Fenix 3 and have been angry at this watch many times. Mainly because the straps disintegrate after about a year of use (I usually train 3x weekly). And Garmin won't honor the warranty. Now I have one from Ali Express in stock, because I won't buy originals from Garmin anymore. I bet it will last as long as the original. Even every regular Casio watch lasts longer. The other thing that bothers me is the heart rate strap, which luckily delaminated a couple of months before the warranty expired, so they replaced it for me.
But when I went to look at an equivalent Suunto, I got some angry user reviews again, so it really doesn't matter what you take. Each has its own minuses and pluses. Of course, you have to compare products of the same generation, so you don't compare Fenix 3, which is already a 3-year-old model, with some completely new Suunto watch. Here in Slovenia, there seem to be more Suunto fanboys, so you'll get more recommendations for Suunto.
With these watches, it's like this. If you only plan to hike in the hills, it probably pays more to have a phone, which you already have anyway. From my experience with phones, they have more accurate positioning than watches, even though my watch has both GPS and GLONASS enabled.
Watches, in my opinion, perform better for runs, where the phone bounces in the pouch or belt and it's awkward to pull it out during the run to check the time. But if you're more of a hiker and have a backpack with an integrated pouch on the side belt, I'd almost rather just have the phone. I occasionally use the phone for maps and navigation anyway. Until these watches become a bit more smart, like e.g. Apple Watch, in my opinion it's almost pointless to waste money on them just for the hills.
What I like about this watch is that I bought an additional Tempe sensor and can monitor the external temperature live. In winter, it somewhat fails, because even if you have this sensor in the most distant part of the backpack from the body, body heat still raises the temperature by a degree or two, e.g. at -12°C.