I have the PRO700's and they do a couple things right, but I don't think I can honestly recommend them. Maybe the issues I have with the PRO700 have been addressed, but here's what bugged me about them.
Not Comfortable, The earcups are too small to achieve a proper circumaural fit - your earlobes will be pinched against your head, and your ears will be touching in several places inside the cups. They are also quite heavy. The PRO500's look fairly identical in this respect...
Honky Enclosure, Something about the cup design on the PRO700 makes upper mids painfully honky at times. What's interesting about this though, is it is not restricted to sounds coming from the headphone, but any sound coming through the enclosure at or around those frequencies. The tones at each metro stop in Montreal are painful when wearing these. And the crazy thing is, when the upper mids aren't honking, they're recessed!
Mediocre Isolation, It's just not that great - these would not cut it in a club/party environment, I'm surprised they're marketed as a DJ phone.
Questionable Construction, Parts of the PRO700's seem bomb proof, others seem really really cheap. I've filled in a number of hairline fractures with superglue, and even repaired a full-on crack once already.
They do sound good everywhere except the HonkZone (tm) - the bass goes quite deep (but in a surprising small quantity for a "DJ" can) and is quite quick. The upper end of the spectrum reaches equally far, and is quite crisp and fast. They make good electronic(a) cans - the problem with the upper mids made them horrible for rock or anything not made of inorganic bleeps and bloops.
They are quite efficient - I used to use them out of a MD recorder for at least a year. They certainly benefited from more power, but were totally listenable.
They are gorgeous looking - superficial, sure, but they look badass - as do the PRO500's.
If your looking to kill your ears, they can handle fairly insane volume levels
And looking at the photos on audiocubes and audiotechnica, the PRO500's look like they use the same enclosure - which is really a shame. While my experience with the PRO700 is no solid indication that the PRO500's suffer from the same problems, I would hold off until you get a genuinely positive response.
