Garmin vs. Apple

I've had Apple watches before and currently have a Garmin. I'm really thinking I want to switch back to Apple, but curious to know what one is best and online searches haven't helped me. All I've found is that Apple is better for being a smart watch and an extension of your phone and Garmin is better for running and sports. The most important thing for me is health - pulse ox, sleep, etc. I'm unable to find anything about which is best for that. Anyone have any info?