Hello, first time poster here.
Here is my brief review of MDR-1000X. I have purchased them on German Amazon.
Sound
I am not an audiophile by any means and the only HP I can compare these to are budget Sennheiser HD 215 II.
Over bluetooth MDR-1000X sounds a bit worse than wired HD 215. These are my first "serious" bluetooth headphones so I wasn't really sure what to expect. It's a bit disappointing but the sound quality is ok-ish.
Over wired, quality wise they sound about the same as HD 215 except for bass which is kinda non existent on HD 215. The sound character is different of course but it doesn't occur to me the sound is any better despite MDR-1000X being 5 times the cost.
Build
The leather polish on earcups is nice. The "creaking" issue is real and is coming from the plastic construction exactly as already mentioned in this thread. To reproduce, simply move your jaws
Luckily, it is very easy to deal with. I temprorarily fixed mine using two tiny bits of toilet paper (creaking completely eliminated)... I will buy a dry lube and hopefully it will be just as effective and more permanent.
I wasn't really expecting the creaking noises from HP at this price range. Really disappointing but easily solvable with some DIY.
As for the rest, it's solid. They look decent and are comfortable enough for longer wearing sessions.
ANC
I am unfortunate enough to live in an aparment with a psychopatic stomping upstairs neighbour and bad sound isolation overall. ANC was the main reason of my purchase and boy did they deliver. I would love to have some direct comparison with Bose QC35 but the ANC here is trully brilliant and saved my sanity. I imagine the voice mode is good for traveling and the ambient one feels a bit gimmicky. Seriously I am not that lazy to just lift one earcup especially when I need to do the same body motion for ambient mode activation + the noticeable delay before it gets activated.
If no music is playing and ANC is on, one can hear the background white noise but it doesn't really bother me since I am forced to sleep with earplugs and a speaker blasting brown noise because of psycho neighbour
Overall I am suspecting these headphones are not built to last and will self-destruct just few days after warranty period. Still, I don't regret my purchase mainly because of its superb ANC.