Durability 945 vs 935 vs 920

I'm not sure this can be answered. I can tell you I bought the 935 in April of 2017 and the 945 in May of 2019 and both are still going strong. 

Bought my 945 in May 2019 (while preparing for the Berlin and NYC marathons), been wearing it 24/7 pretty much since then. Solid watch, no problems with it. (I did get a scratch on the edge of the screen which was a bit of a mystery, but since it's not covering any of the active area, it doesn't other me too much. Otherwise the watch looks and performs like new)

My 920xt was very reliable too.

Maybe it's a crack not a scratch?

You won't get any objective result to your question from couple answers on the forum. Even if a few users reply negative experience it is still biased sample size and tells nothing about real performance and build of FR945.

945 user for over 2 years. I've been wearing it 24/7. 12 - 15 h of weekly recorded activity (trail runs, park runs, indoor and outdoor cycling). 

This being said, I don't expected anything else from this watches. I only had to buy recently a new fastener ring. Otherwise not a single freeze during or outside of an activity. I'm not measuring battery life precisely but even after 2 years of said usage, I don't see a significant drop in battery lifetime.

Same

Using 945 since 8/2019 means 2 years now. At 2019 battery lasted 30hours (run with navigation with map on display). Now, under the same conditions battery lasted 12 hours only. One need to know this and use small powerbank. Otherwise no problem with the watch. (it was raeaction to gtom comment)

Honestly, I can't tell 100%, but looks like a scratch to me. Happened the day of the Chicago marathon 2019 while I was volunteering handing out water. Wasn't there before, but by the end of the long shift. No idea how it happened. So it's been almost 2 years, hasn't gotten worse or impaired the functionality (but a bit irksome).

otousignant said:

today the watch turn always

What do you mean by this?

otousignant said:

The watch display garmin all the Time without stop

Just to make sure. Here's the 920XT master/factory reset prodecure. It's a little tricky and requires some dexterity. I've done it several times.

This will erase all user data and set watch to out-of-box day 1 condition.

• Power off device. If unit is frozen, power off by holding the power button for 30 seconds until the screen goes black.
• After device is fully powered off, hold 2 right buttons simultaneously
• Press and release power for 1 second (keep holding down the 2 right buttons)
• Wait for 1st beep, then release top button
• Wait for 2nd beep, then release bottom button
• If successful, you will be prompted for language
• Follow the remaining on-screen prompts for initial setup
• Sync with Garmin Express
• Place watch outside with unobstructed view of the sky for 30 minutes