Mine Arrived Today. I have only had a few minutes to listen so far, but so far so good. Here are my "immediate impressions".
1) They sound as good as my Beyer DT231 (which were only $59 shipped)
2) They sound very similar as well - sound signature is almost identical in fact (to me this is a good thing)
3) The HD25-1 II did come with the extra velour pads and foam, a 1/4 adapter and a headphone sack, the DT231 come with the 1/4 inch adapter.
4) The HD25-1 II are heavier and have a heavier clamping force on the head, so they are not as comfortable as my DT231.
5) The Beyer are circumaural vs supra-aural, but the cups are too small to fit completely around my ears but it isn't uncomfortable.
6) The main advantage is the HD25-1 II isolate external noises more than the DT231
7) The second advantage of the HD25-1 are they are slightly more efficient, so 50% on ipod volume = 60% on the DT231
8) The third advantage of the HD25-1 is the ability to upgrade the cable to upgrade the sound, while the DT231 are what they are.
So, for the same sound signature, if you have to save money (half the cost, or want lighter weight/clamping, and less isolation) get the DT231. But, if you need more sound isolation and want to upgrade cables and sound later, then get the HD25-1.
Either way, the sound signature is pleasing, while not as detailed as my HD600 or HFI700 DVD. Both the HD25-1 and DT231 are much more efficient than an HD600 which need 100% volume vs 40-50%.
Compaired to open-back portable headphones, they also have more extended frequency range vs the PX100 which sound dark, and don't have any grating upper mids like the iGrado have with some program material.
