Not sure if its worth getting if you already own other quality headphones like the M500's or WS99. It is a different presentation so it can be worth while. I like both Onkyo's, especially at the given price but its not better than several other gears in this thread. Neither of mine have much over 50 hours of burn in so only time will tell but I have a feeling more changes will come, especially with these cables. I would still recommend them as a safe purchase.
So at this point you think the sound in the M500 and the WS99 is better than the Onkyo headphone? I mean the premium Onkyo cable headphone and the WS99 about the same price now (or within the same vicinity).