Cons:
- Really Bad Bluetooth Connection Management - God forbid you have 2 devices connected at the same time! audio loss is only fixed with reboot. Nearly impossible to connect it to a Win Laptops
- No firmware updates!

Pros:
When they work, they work really well;
- great sound
- great noise cancelling
- feel/look great

I've written a review before about these headphones, but back then, only 3 weeks ago, the connectivity was not this bad.
Now, my Dell G3 2019 Windows 10 laptop cannot connect to the headphones, they enter a loop of connecting and powering off and on. It's horrible. And connecting to my iPhone 8, is just as bad: same loop but only one iteration.
I removed the device, restarted the laptop and tried again the first time because the connection was continuously breaking up. Now, the loop, I can't listen to my laptop music.

Sennheiser really screwed up this time. I'm gonna ask for a refund and return the headphones.

I’ve had my Sennheisers for 3 years and have enjoyed the sound quality but the battery is no longer holding its charge. I would expect for a product that isn’t cheap to last longer than it does. Probably wouldn’t buy this brand again.

So i was in the market for a new pair of headphones and i did a bit of reasearch and decided to give the sennheiser pxc 550 head phones ago and have not regretted them comfortable bluetooth to everything unlike boes or sony i also have sony and it has problems bluetoothing to all devices but no trouble with pxc550 and sound just as good as bose and sony for a slightly cheaper price, look into it guys you won't be disappointed.

I purchased this noise cancelling machine as I travel by air a lot.
It works well on the plane block out the engine noise I can enjoy watching movie with better sound quality.
When I first tried the headphones on I felt a little queasy. I searched on line it seems some people with the same problem. It's not product related it's more like individuals and the inner ear balance thing. I soon got used to them and the queasiness is less obvious to me.

The answers are as below:
- music, movies, news,...
- It is but because I love it, I do not want to make it sweaty so I bought a cheaper one for these activities
- It could be louder
- It is good

Just received today, and was impressed by all facets of these very comfy headphones. Packaged in a travel pouch with cables and adapters for all aircraft, the sound is impressive, clear and full. Certainly an immersive audio experience. Light, and easy to use at the touch or swipe of the right side headphone. Pause, play, FFwd, Next, Back, Volume +/- or answer / mute calls......it's like learning a new language, but very easy using one finger....Easy pairing to multiple devices and easy charging with included USB cable (no 240v charging adapter though)

Have had these headphones for 8 months and have loved them. Fantastic noise cancelling and the touch swipe feature is really handy. I wear them on my commute and they're good for travelling on loud planes. The wireless range is great and the sound quality is fantastic. I've also worn them to the gym and they've been really comfortable.

great sound quality. Bass in particular is good. I find it a bit uncomfortable but its ok for a few hours at a time.

Overall - very happy with my purchase!

Sound - great
Comfort - great
Build - great
Price - average
Overall, a good quality product which comes at a cost but proves its worth. You will not regret this purchase. Touch interaction on the sides. Noise cancellation works good.
A great deal.

These headphones are extremely comfortable and offer some great features. They stop what your'e listening to when you take them off, you can adjust the volume by sliding your fingers along the side of them, the amount of noise cancellation is adjustable, the wireless range is fantastic, and the battery life is great. I use them for music and movies, and can't fault them. The only minor criticism I have is that I would like to be able to turn them up louder. I chose these over the Bose QC35, and I am more than happy with my choice.

Sennheiser PXC 550 sounds great with pretty much everything once you make a few adjustments via the CapTunes app (go into the Director Effect Mode and make adjustments).

I have for instance set the customisable Director Effect Mode as:

Boost = Thump
Spatial = Near
Reverb = High
DLC = On

You can then press the Effect Mode Control button (on the right ear cup) and a Director Effect Mode will be added to the available options. Noise cancellation is ok not as good as the Sonys or the Bose but these do look better for mine. Very comfortable as well. Highly recommend.

Great headphones the sound is great and is something i was expecting from a brand like sennheiser, the noise canceling is very effective & the battery life seems to be very stable. I would happily recommend these to other people.

I use these for long flights (7 to 8 hours) and it doesn't hurt. They are really comfortable. Sound quality is decent. Battery life is great too.
The only thing I find annoying is that when the battery is low, around 20%, you get this annoying battery low message every few seconds.

Man I love these things. It's just a sunshine-on-a-crisp-winter-day feeling when they hug your ears and deliver smooth audio goodness.

They worked out of the box. The battery life is awesome. They connect really easily. Are simple to use. Noise cancellation is wonderful. And they sound great! Honestly they're that good that I want to finish my review here. There's just no more to add.

If you're thinking of purchasing wireless headphones, as of 2018/19 these are hard to beat. Best Christmas gift ever :D

Very happy with the sound, quality and build. Used these with laptop. Recommend trying these on instore. I made the mistake to buy online without trying them on. I have a wider head, the earpads clamped and gave me a headache. My brother is very happy with these though!