To add a contrasting anecdote for balance, the only issue I've had with B&W headphones (I've had P5, PX, and now have PX7) is that the arm of my PX snapped - probably in part due to how I'd cram them into my backpack and that I got them early in the product life when they shipped with a quilted fabric soft case.
Despite it probably being as much an issue as my care as the product packaging, B&W replaced them rapidly without complaint and I've had no issues since.
Also the carbon composite construction of the PX7s is one of the best I've seen. I tried a pair of AirPods Pro which felt premium but were so uncomfortable due to the weight and design causing huge pressure on the contact points with my head. PX7s feel very solid but don't have the weight penalty to go with it.
Despite it probably being as much an issue as my care as the product packaging, B&W replaced them rapidly without complaint and I've had no issues since.
Also the carbon composite construction of the PX7s is one of the best I've seen. I tried a pair of AirPods Pro which felt premium but were so uncomfortable due to the weight and design causing huge pressure on the contact points with my head. PX7s feel very solid but don't have the weight penalty to go with it.