Extremely disappointed with the noise-canceling - it is nothing but a ...
923374
Extremely disappointed with the noise-canceling - it is nothing but a "sock" over the mic itself and doesn't work at all. If you are skyping and taking notes on a keyboard that noise gets picked up.

Stay clear of this product and shame on Sennheiser for mislabeling.
1795163
Received the model with no noise cancellation, returning..
2803421
Mine must have been defective. Sound quality was terrible. There was no no noticeable noise cancelling.
4403419
Very disappointed with these: Noise Cancellation on/off didn't see to make much of a difference. Pretty heavy, and the square earpiece is not that comfortable.
4281988
You can't even hear what the person is saying because it picks up and amplifies all the outside noise. They claim they are noise cancelling. I feel as thought I wasted my money because I ended up buying a different pair/brand that is actually noise cancelling.
573785
I was disappointed when, after wrangling the clamshell packaging off of these guys, I felt really cheap headphones. The plastic container that holds the battery feels like dollar store garbage.

The worst part, however, is that the "noise reduction" mode actually ADDs a tinny buzzing to the music. No matter how loud or soft I play my music, I can still hear it and it drives me insane. Imagine a very old tube television on mute, to get a feel for the sound I'm describing. It doesn't seem to do any actual active noise canceling.
2835506
Do NOT waste your money if you are expecting even 25% of the Bose noise cancellation. I wish I could return these for a full refund by I've waited too long since I purchased them. I bought these for a trip to Europe and did not test them before the trip. I was very disappointed on the plane to say the least, these are awful. Sony should be ashamed of itself for labeling them as noise cancelling.
2074721
I got these the other day, figuring what the heck, cheap and noise cancelling!  And lots of good reviews about how great they are.  I don't get it.  Not the slightest noise cancellation at all, not very comfortable.  I would definitely not recommend these, even at this price!
2783736
DO NOT Waste Your $$$$ !!!  Ok, if you want a secure earpiece.
However, noise reduction was VERY unsatisfactory.
Simple finger presure in ear blocked out much more noise that these earplugs.
Very disappointed!
I am a dentist, so I am familiar with moldable materials.
I do not believe it was technique related.
290425
These may be ok if you don't mind your gamer friends hearing your mom in the background asking you to clean your room.  I purchased these for a call center environment and there is ABSOLUTELY no noise cancellation.  The background noise is terrible.  These guys really dropped the ball, considering the cool look of this headset.  The Sades SA-901 is the model to get if you want not only good quality, but noise cancellation as well.
4498687
- definitely not noise cancelling, not even close.
- poorly designed (have had my hair caught in them painfully, frequently)
- difficult to pair to more than one device (had to go to Apple store to figure out how to pair to my mac after my iphone - its a different pairing process after the 1st pair, which isn't very clear from the instructions)
- aux cord breaks easily (have had to replace mine twice in 10 months)
- charging cable breaks easily
- HORRIBLE and extremely lackadaisical support team. Took over 3 weeks for a response the two times I wrote in for said aux cord replacements (it's a known issue on their end, the support agent admitted they broke all the time).
- I've received compliments on the look of them though

*Highly recommend not wasting $200 on this piece of junk, unless you'd drop that kind of cash for a stylish, nonfunctional headband, which is essentially what these are.
719986
1) too heavy!
2) my ears sweat when wearing them beyond 30 min.
3) can not charge it while listening to music. you need to stop listening to music, charge it, and then resume.
4) the noise canceling feature is like a joke. no difference before and after turning it on.
5) the microphones are basically useless. no one hears you if you use them.
1483460
I recently bought these, and they certainly weren't worth the money.

Firstly, the "3 cap sizes to fit your ears" were very badly thought out - the headphones come with medium sized caps attached, and in the package mould is a single small one and a single large one. There wasn't even a space in the packaging for a second of each. I am not a mutant - I have two ears.

Secondly, the "active noise cancellation" does not work very well at all. It appears to be only an amplifier (music players have a volume limit built in to stop you damaging your hearing, and this deftly bypasses that,) and even at the most optimum background noise (according to the manual thats a continuous 300hz sound) they have no audible effect except for a quiet, constant background static.
1085773
These are a joke for noise cancelling. Anyone who has put on a set of Bose Noise Cancelling headphones knows the amazement that goes over you when noise reduction happens. Turning on music to cancel out background noise?...Don't all headphones do that. Here was my test. Put these on... turned off... and with no music... and walk outside. Birds chirping, sound of a cool breeze, and cars passing by. Now you flip that switch and it should all fade out...without the music!!! These don't do that. As a matter of fact...I couldn't tell a noticeable change. Now if I turn on music and crank these puppies up...then the aforementioned sounds vanished. But so did the bird, cause the tunes coming from the earpiece scared him off. My wife told me that I couldn't take these on the plane cause the other passengers would need Noise Cancelling headphones to drown out my Pyle Home PHPNC45 High-Fidelity Noise-Canceling Headphones. Now i thought that was Funny!!! These didn't even last 24 hrs in my home...they couldn't drown out the sound of my wife breathing heavy while she slept on the couch with the dog. I boxed them back up and returned them the very next morning. My Bose just arrived and I felt compelled to warn others while wearing them. And as I was writing this review...no joke.....If not for my dog I would have missed  the UPS man deliver another package because of these Bose. I suggest to anyone to go to the busy as hell, Apple store, and see how real noise cancelling headphones sound. Don't be dupped!!!
2634998
Noose cancelling is horrible. There is a constant  hiss when using this feature. One turned off the sound is identical and in par with any mid range headphone. Amazon is currently selling these off at $17. I wish I paid $17, that's what they are worth.
3869043
Great headphones if you have noise canceling turned off... however, when on (the reason I bought them), there is no music.  All you can hear is static which is designed to drown out the background noises.

Luckily, got these on a lightning deal for $17, but would have been more than angry if I paid full retail (or even prime rate of $50).

Save your money, DON'T BUY THESE!
1270037
the title says all.  I don't know about the noise-cancelling feature since I haven't had a chance to test it.