You are comparing apples to oranges. They are both totally a different style. If you prefer on ear headphones then the Solo 3's are what you are looking for. The AirPods are in ear so if you prefer that style then go for those.
I can't wear on ear headphones (my ears hurt after a bit) so I have AirPods and Powerbeats3's and I love them both, but the AirPods are my daily use headphones. For everything, gym, work, etc. I use the PB3s to sleep with since they have the ear hooks so they don't come out over night.