I've been listening to my friends Ether C for about 4 weeks. I'm still not sure what to think of it, beautifully built headphone - one of the best I've seen. The tuning for me is not very accurate, it seems like that typical tuning to try extract details for the sake of a more natural FR - Nothing wrong with the headphones, they do well with that tuning but I need that low bass, natural curve and a bit more elegance as opposed to dry, slightly brittle even on my Gumby + Tube hybrid amps.
Extra points for the ear cups, love em.
I just got mine yesterday. Out of the box, the sound quality has a long way to go before it beats my HE-400S or the Oppo PM-3. I realize the break in period is long so I will remain patient.
Besides sound quality there are few things that I believe need improvement and /or correction:
The Bad
3. Cables are overpriced. I did not get the DUM cable. If this cable was "voice" with headphone it should be included free.
The Question
I believe the Oppo PM-3 and the HiFiMan HE-400s are at the pinnacle of the price/performance cleft. The question is will the performance of the Ether justify the price difference of $1,100-$1,200? In 150 hours or so, I will have to answer that question.
With regards to the Dum cable, it is "free" if you buy the DUM cable bundle. MrSpeakers give you an option to buy a bundle with a less expensive cable. If the latter option were not available, you would get the Dum cable for "free". In other words, nothing is "free", not even the "free" data on your phone plan. You just have to decide how much "free" you want to pay for.
As for price performance, you very well be correct. No one buys summit-fi gear because of its price/performance ratio. The law of diminishing returns is the prime directive in audiophile land.