The P5 suffer from a disgusting design flaw: Under the magnetically connected ear pads, the headphones have a soft fiber-like material that's glued in. The glue will melt and leak between the contact points in a few months, which will stain white t-shirts etc.:
The importer first claimed they fixed this issue mid-production, they did not. I went through FOUR pairs. Every. Single. Time. the glue melted.
I wrote to B&W about them having a systematic problem in their manufacturing process, they advised me to contact the importer for a replacement pair.
Then came the P5 series 2 which the importer said would fix it. Finally... Except, it did not.
When I contacted the importer about the problem being still present, they flat out refused to replace the headphones, but instead offered a discount for PX headphones. I told them I would've annulled the purchase like the Finnish law allows me, had I been made aware it would never be fixed. I also told me I wouldn't pour another cent in B&W products.
Also I found an entire site dedicated to the design flaw in the PX, which I alas, can't find now.
To conclude: Do NOT buy B&W headphones / consumer loudspeakers. The company does still manufacture high-quality high-end loudspeakers, I've been satisfied with the CM1s and no complaints after 10 years of use.
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.
https://imgur.com/a/W2i0pPa
The importer first claimed they fixed this issue mid-production, they did not. I went through FOUR pairs. Every. Single. Time. the glue melted.
I wrote to B&W about them having a systematic problem in their manufacturing process, they advised me to contact the importer for a replacement pair.
Then came the P5 series 2 which the importer said would fix it. Finally... Except, it did not.
When I contacted the importer about the problem being still present, they flat out refused to replace the headphones, but instead offered a discount for PX headphones. I told them I would've annulled the purchase like the Finnish law allows me, had I been made aware it would never be fixed. I also told me I wouldn't pour another cent in B&W products.
Also I found an entire site dedicated to the design flaw in the PX, which I alas, can't find now.
To conclude: Do NOT buy B&W headphones / consumer loudspeakers. The company does still manufacture high-quality high-end loudspeakers, I've been satisfied with the CM1s and no complaints after 10 years of use.