Also ask any serious Garmin watch user about their charging/data contacts. They start to rot away after 1-2 years of being exposed to sweat.
I don't think I've ever heard anyone complain about that, and I know a good amount of people who use Garmin watches. My own forerunner is still going strong after 5 (I think) years of use, with multiple runs a week for most of that time.
Just looked at mine and wondered whether I should 3D print a cover for the contacts from TPU. Thanks for the idea!
edit: Done. :-D Better safe than sorry.