Keep in mind that the T50RP MKIII (T30/T40 and all Fostex derived variants using OEM jacks as well) have a history of headphone jack failures. They sound awesome for single ended cans, but the jack used to hook the cable to the cans is well known for failing. The locking mechanism is nice, but it doesn't fully protect the jack from lateral stresses. A year or so of *hard* use will cause the jack to start having intermittent connections with the TRS plug. If you're prone to getting your headphone cable tangled or snagged, you'll most likely see this problem.
Even with that complaint, they're very worth the price. The sound is amazing and they're cheaper than the T60RP (which doesn't have the jack problem, but has its own problems). Don't sound as good, but eh, price versus performance.