The ear pads, combined with a low-pressure headband, mean that the P5 is quite comfortable for long periods. I would rate it as among the most comfortable in my experience, though heads differ, as may your experience. This test took place in December, so I couldn’t test the heat/perspiration factor using our standard Texas blast furnace simulation technology, but indoors there was no issue.
The ear pads pivot so that the P5 lies flat in the included case. The P5 is therefore pretty easy to store in a backpack or briefcase, but the ear pads don’t fold inside the headband, so the footprint is large enough to preclude putting them in a purse or other small case.
The cord is short-ish at a bit over 1 meter. I think this is ideal, but your circumstances may make you wish for a somewhat longer cord. The cord is also very thin, which helps with packing and reducing the tug factor.
I also found the P5 fully capable of being driven by an iPhone 4. I used the P5 on a flight from Chicago to Austin and volume was more than adequate. A mic and remote cable is included for iPhone use, meaning that the P5 can also serve as a headset—a feature prized by many contemporary listeners.
A significant part of most headphone reviews deals with the inevitable difficulty of reproducing upper midrange and high frequencies in a way that sounds natural. Basically, our recordings, ears and brains are designed for music that is reproduced by sound sources that are located some distance from us, and are not designed for music reproduced a fraction of an inch from the ear. Headphones therefore have to deal with the nasty issue of HRTFs (head-related transfer functions), which is basically how our heads and outer ears equalize sounds coming from the outside world. Since headphones for the most part bypass the head and outer ears, the headphones themselves have to have built-in frequency response deviations that simulate what the HRTFs do.