They sound good but break easily and are near impossible to fix. Mine broke after a year, meanwhile my PXC-550's from 2017 are still going strong, cost $100 less and only needed a battery replacement.
Discussion
The XM3’s did break on me after a couple years also. But I liked the quality and feel a lot and I got the XM4’s promising myself that I’ll take better care of them this time
I wish your headphones a long life. I will never buy headphones from Sony because they wouldn't cover the failure under the warranty, despite them breaking inside of the case, and showing them a photo that clearly demonstrated that the part was defective (it had air-pockets where the breakage occurred, shoddy injection modling)