I am on my second 935. I returned the first in a week as it kept on freezing - especially on sync - I'd get the Garmin Triangle of Death (GToD). Once the freeze also started happening on runs I called garmin and after trying a few fixes they told me to return it. The second watch did the same.
I have a work-around for the GToD if your 935 keeps freeing. Don't bother clearing the memory and formatting and all that stuff (didn't work for me). The only thing to work is never to connect the watch to your phone. This is a pain in the ass and it means you cannot use all the features that are sold as part of this watch, but if you have an iPhone7 or 8 (I've not tried the others) there appears to be a problem with 935xt that crashes when connected - I've tried two watches, both the same.
So I've added my work and home wifi to the watch and sync only by wifi or plugging into my computer. no more GToD. I hope a better fix is forthcoming.
