My experience with wireless charging the 2nd gen AirPods (still waiting for my Pros to be delivered later today) is that the case is very conservative when it comes to temperature. Because the battery and electronics are all crammed into such a small enclosure, the case tends to warm up during wireless charging. With a larger device like a phone, there is more surface area to dissipate the heat (and the enclosure is usually made of metal, which also helps). That's not the case with the AirPods. Once the case gets too warm, it will stop charging until things cool down again. Then, it will resume.
Bottom line, wireless charging is very convenient for charging the case overnight. If you need a fast top off though, I'd stick with wired charging. Since the case can recharge the AirPods so many times, I find I am only charging the case 1-2x per week. So, I don't mind just sticking the case on my wireless charger overnight whenever it gets low. I'll be interested to see if that pattern holds with the Pros.
