The P5's closed-back design does a good job of keeping out unwanted noise, and, while you won't be completely isolated from the outside world, it's enough to keep your attention on the music.
The P5s are aimed squarely at the iPod and iPhone user base. While the 3.5mm jack (a 6.5mm adaptor is included) will work with most MP3 players and computers, the P5s' cable also features an Apple-approved remote control near the top of the cabling.
When using the headphones with an iPod, you'll be able to use the remote's three buttons to skip tracks and pause, which should save you rummaging around in your pockets. Plug the P5s into an iPhone and you'll be able to take calls using the remote, speaking into a discreetly housed microphone. iPhone users will undoubtedly appreciate this feature -- anyone who's attempted to unplug their headphones while retrieving their phone from a pocket will know how annoying it can be to take a call when listening to music.
One complaint is that the included cabling is rather delicate -- it's quite skinny, and liable to tear if you're not careful. You could switch this cable for one of your own (it plugs in via a socket beneath the left earpad), but you'd lose the useful remote control.
The Bowers & Wilkins P5 headphones are expensive, but they offer high-grade performance, and you could easily spend about five times as much on a set of high-end cans. We simply can't imagine anyone not liking these headphones -- they offer sturdy build quality, a beautiful design, some really neat features for iPhone users, and sound quality that shines in every respect. This is an impressive first attempt from Bowers & Wilkins, and we can't wait to see what the company does next.
If you want some more advanced noise-cancellation capability for a similar price, take a look at the Bose QuietComfort 15s.
Edited by Charles Kloet