I haven’t used an around-the-ear bud in many years. Do you think the Powerbeats Pro would work well under a bicycle helmet (where the straps typically pass just in front and just behind the ear)? I wonder if they have them open at the Apple shop - I could always swing by with a helmet and try.
Have you tested how well the Flex pairs with multiple devices? That’s one nice feature of the AirPods, at least within the Apple device ecosystem. At that price, they might be my best option, but I haven’t heard much about the chip they use (vs the H1 in the AirPods and up-market Beats).