I have tried most "in-ear" headphones / headsets. And so far without fail - every single one has been uncomfortable to wear. I would get itchy and sweaty in my ears - and when you run often that is not nice.
So for a long time I have been alternating between Trekz bone conduction (with ultra bad audio quality) and normal AirPods - and AirPods wore my favorite. They have never fallen out from running or exercise. But they do start to corrode if you are not vigilant in cleaning the sweat off. Then you get the green corrosion on the charge contacts. So I have cleaned mine with Deoxit from time to time. My first set the Microphones died - but got replaced under warranty. After I started cleaning with Deoxit I have not had more issues with corrosion.
But since all my bad experiences with "In-Ear" I was really on the fence about the AirPod Pro's. I tried the over-and-in ear PowerBeats Pro - but they are uncomfortable for me as well.
So a week or so after launch I thought - nahh - probably won't work for me like ALL other In-Ear - but I'll try a pair. (After trying 15-20 in ear products - expectancy was very low)
I then bought a pair - and I'm a convert.
I can use them for hours without irritation. The in ear shape fits me fine (not round like the rest - but slightly oval) - and the "ventilation" built in keeps me from the sweat build up I had with all the other in-ear products.
There are some issues /bugs I have found:
1. Activating/Deactivating noise cancellation via Siri - will on mine - make the audio between left and right ear become out of sync. You get a lovely echo effect. Cure : Put back in case for a bit - or Reset them.
2. I have issues with paring it with other Bluetooth devices. If my Bluetooth "Transmitter" X has been paired with the AirPod Pro's - and its Bluetooth is "on" - it will somehow OVERRIDE the any iDevice currently connected and playing. (Sudden disconnection - very annoying during a call...)
I do wish that Apple could find a squeeze command for Volume Up / Down though for 3rd party Bluetooth connected devices. Not all Bluetooth output devices have volume controls. Maybe Left double/triple squeeze? And Right for forwards/back? Or maybe completely configurable?
Transparency works "ok" but could be a lot better and maybe intensity adjustable?. Some things get slightly overpowered - while others sounds disappear.
But I do love the AirPod Pro's - the comfort - and the noise cancellation just makes them my new favorites.
Noise cancellation might not be up to Sony/Bose standard but it is 90% there - and 90% is enough in most cases. And they are a lot more comfortable to wear "napping" on a flight than my QC35's. Yes they need recharge after 4'ish hours.. But worth it.
that was my 356 cents ...

I'm happy with them - more than happy.
Happy Thanksgiving to all in the US