Most of those headphones need good amps to sing, and I don't think these headphones would destroy those listed above especially considering they are technically the best HP's around.
From what I've read, these are on par with the HE-500 which is not a negative thing at all, in fact it would make these a great bargain considering the lack of amping requirements
I used them all above with a Burson Conductor coming out of both a computer and an iPhone 5s (take that as you will) and in the end was impressed with none of them enough to purchase them. I took a complete gamble on the PH6 and from the MOMENT I put them on my head I knew it was the right decision.
These are so far above the HE-500 it's ridiculous, and even above the HE-6. Now if you're someone who just prefers open-back then this will not be the case, but the PH6 coming straight out of a Macbook Pro yielded a superior experience to the above listed coming out of the Burson.
The thing is, I really, really wanted to like the HiFiMan and Audeze. I had the money, I was ready to buy my first big boy audiophile setup. But I sat listening, going through this song and that, hearing the strengths and weaknesses, understanding perfectly well what those headphones did beautifully, but I just could not say that they were worth the purchase. I listened to the PH6, immediately was grateful I hadn't bought the others, and am still grateful now.
I feel the need to really impress upon you that this is not me justifying spending less money. I was fully prepared to drop a decent chunk of change on whichever sounded best to me and the necessary hardware to go with it, but I just couldn't. The sound wasn't there. Now sure, I'm willing to bet if I could get some LCDX or whatever else is even further up the ladder I'd find my winners, but there was nothing amongst the sub-1500 crowd.