My day job is looking out the windshield of a corporate jet. Over the last almost 40 years (oh my I'm getting old) I have come across just about every headset made. I started with a David Clark H10-40 and still have it.
However, when outfitting our current aircraft I went with the Bose A20. I have used every Bose model beginning with the original. The original was very comfortable but bulky. The second was better. The X I didn't like. There was something with the headband that didn't agree with me. I always got a hot spot from that one.
The A20 is by far and away the best Bose aviation specific model. Ours are wired to ships power so batteries aren't an issue. We wear them for the whole flight in order to keep the noise down for the pax in the back and enhance communications, especially when in a foreign land. In the past week that included (2) 10 hour legs without any discomfort. Many 14 hour days without complaint. Granted, unlike an RV, this is in an air-conditioned cockpit. A hot day, warm cockpit might be a different story. An in-ear setup might be better in that situation but I would be hard pressed to give up an over-ear if the leg distances were oven an hour or so.
Another option that hasn't been mentioned that is almost as good as the A20 is a Bose QC25 with a uflymike headset.
https://uflymike.com/pages/what-is-harmony
I used the previous model before Harmony with a QC15 for quite a few years prior to the A20. Even more comfortable than an A20 because it's lighter with the added benefit of having a great headset if commuting. The single AAA battery lasts for a long time. Easily enough for a Europe round trip from the west coast. I have a Harmony on order to try so I can't speak specifically about the new model but the previous mike worked fine and the headset is the driver for comfort anyway.
"When" I have an RV8, I will have 2 of these QC25 / uflymike setups dedicated to it.