I've had the P5 for almost a year. Amazing set of portables. Not only do they look good but they started sounding good as well after 3-4 months
With my drivers fully warmed up to the task and the foam earpads also slightly stiffened up, the sound really changed alot. It now is a little sparkly at the treble, with hints of sibilence in some tracks, what within the first 3 months it did not have. It was frustrating for the first 2 months or so where I consistently battle the temptation to sell the P5 for something better. It has since become my undisputed lover (until.. well.. later today, where the Ultrasone Ed8 come in). I've thus sold every other earphone/headphone I have except the P5 which I am very very.. undecided about letting go. And the GR07 which I will use as my IEM of choice.
The slightly dark and muddy feeling about it also is lifted off slightly, and its more warm/sweet sounding than muddy. The bass extension never improved however, and is slightly shy at the sub-bass department, where it rolls off quickly. But this requires an investment of love and time. The leather of the P5 also yearns more tender love and care compared to the HD25s. I do condition and buff the leather every 3-4 weeks or so.
It would also be easier if the p5 would be the only headphone you use constantly, coz then for the first few months there is nothing to compare to that can make its early weaknesses more evident. I used to own a million headphones so their traits are slightly more obvious to me but I held on!!
Most P5 bashers are those that have not spend enough time with them, like those who tried them in store, or those who sold them off within 1-2 months of purchase. If you read into several threads you'll find that those who held onto the p5 for a longer period of time truely appreciates them.
Comparatively, the HD25-1-II's are slightly more unassuming, taking the neutral path with a lighter body in its sound (compared to the meatier, warm P5). Great replaceable parts and indestructable.
Other portables to try are the ATH ESW9, which I think sounds equal to the HD 25 I II cept they look better!!
And the Beyer DT1350, which IMHO is probably the only portable sub 400 headphones that actually beat the B&W p5 in sound. They look horrible when worn on your ears..
Edit: Loving how my last post as a 100+ member is about my beloved p5... and now i'll make my first 500+ post about the Edition 8