I use a garmin edge because I don’t like to run down my phone and find it annoying to wear a watch while cycling. I also find it easier to glance at all the important useless numbers on a screen in front of my face rather than one on my wrist.
FWIW, I’d always sync with strava because you’re likely to switch platforms at some point (or your platform will disappear because reasons) and strava syncs with pretty much everything and seems to be the one that one the tracking wars. If you ever want to look back on something a decade from now, your odds are better that you’d be able to do so without a lot of drama using strava than anything else.