I am using the Lezyne Micro C watch. When I’m riding, I have it mounted on the handlebars so I can see it, and use the buttons, easily. I have found the GPS to be very accurate, and it has never dropped/skipped the signal or given me any funky readings. I use it with the matching heart rate monitor, which also works very well.
I primarily use it for cycling, as that is what I want to track data for. I am not a runner, so I cannot speak to that feature. I have used the hiking feature, and it works just as well as the cycling. The lifestyle feature is just your basic step/activity counter, without the HR monitor. I don’t use that much.
For cycling, it is excellent. And I haven’t even used all the features, like cadence/power/etc.