Pros: Sounds amazing.
Can hear people speaking to you without removing them.
Very comfortable once you break them in a little.
Not very heavy when compared to something like the Logitech G35.

Cons: Initially bothered my ears a bit, so I was shifting them around a bunch. After a few days it was good.
Could use a mic, but that's not really what they're for. I'm stretching to come up with stuff here.

Pros: Big balanced clear sound. Open back design is a game changer for me. I was skeptical about the whole open sound stage, but I'm sold.

Best sounding and most comfortable well built headphones I've ever owned. And Less than $150?! buy one for your wife too!

Cons: Wife is jealous.

Pros: These are the best headphones I have owned yet. They are very comfortable on my big head, and produce some amazing sound. After reading some reviews of these headphones I was worried the bass would be a little to weak, but in my opinion they are right in the comfort zone. I would just say that these headphones produce good bass, but not overpowering. Not to mention they are much more light weight than they look.

Cons: non so far, I hope the headphones are durable.

Pros: Seriously good sound and very comfortable ear mufflers, way better than the g930 I had earlier

Cons: none

Other Thoughts: Best headphones I ever owned :D

Pros: Really clear sound and even better if you do the foam mod on them.
I use mine on my Onkyo amp at night for great sound quality and dont have to comprise sound quality with game headsets.

Cons: If you have a android they may sound low if you dont have a mini amp. I heard that iphones have the power to run them.

If your phone doesn't have the power to run them so they get loud enough and retain their bass. FiiO sales a mini amp on this site that will run them great.

Pros: They are nice headphones... i guess. I don't want to hate on them too much because i feel like it's personal preference therefore i'm not putting the eggs through the floor. they do have good build quality and feel very nice.

Cons: No amount of EQ in the world can bring the treble out in these headphones it doesn't matter what i do. also when it says open style it means OPEN don't just shrug it off. my dad was across the house when i had them at 1/4 volume and was complaining for me to turn it down. Also the sound signature is fairly muffled almost like it's coming from another room.

Other Thoughts: my personal experience is truly a 1 egg rating i prefer my old cruddy turtle beach x41's to these (xbox360 headset im using with my pc) and since most of you probably doubt me at this point, yes i am using an amplified sound card, 600 ohm amp, so that is not the problem with the sound. however i feel that most of my bad experience is preference related. if you like a lot of treble like i do and enjoy the sound of guitars being out front in your music, these are not the headphones for you it can't be done no amount of EQ can make it work. maybe i'm naive for expecting this out of open headphones but i feel this review could be helpful to anyone like myself

Pros: Great sound quality. Reasonably affordable for high definition headphones. Comfortable

Cons: They aren't noise cancelling, but don't advertise to be

Other Thoughts: I have been a Sennheiser customer for nearly 8 years and this particular pair of headphones are everything they were promised to be. My old pair of phones (HD555's) lasted me for 6 years of travel and rough ware. My old headphones are built relatively similar to the HD 558's. At first I was a little off put with the longer cord, but I learned to embrace the freedom the cord offered. I have already noticed the level of ease that parts can be replaced on these phones and it should make for easy repair in the worst case scenario. If you're interested in a very sleek, high quality sound pair of headphones you cannot go wrong with the HD 558's. I recommend these phones to anyone interested in listening/playing music, gaming, or simply having amazing headphones.

Pros: The strongest feature of these headphones is the comfort. They have nice clamping force so the headset never feels like it will shift, on larger heads it might be a bit much though. Very soft plush ear cups that don't squeak when wearing glasses like many others do. Good even sealing around the ears. Nice sounding highs and high mids. Breathe well since they are open backed and while their soundstage is small, they sound much better than most closed back headphones I've used.

Cons: Waaaaaaaay too much bass. And not the good kind of bass. Very distorted and loose, so much so that it starts to muffle the mids. If you've only used mid to mid high quality closed back headphones these will sound pretty nice. But coming back to these after using a bass port modified AKG Q701 makes them sound like a murky mess. You also begin to realize how small the soundstage is... like the sound is being funneled straight into your ears. Not realistic at all.

The build quality on these headphones is good, but is also a bit worrisome as the strap and earcups are completely plastic. They don't creak or anything, but it would have been nice to see some metal band reinforcement. Because they clamp so well I was always a bit afraid of stretching them to far when putting them on.

Other Thoughts: I evaluated 16 headphones from various manufacturers from the 120-250 dollar range. I would say these ranked about 6th overall and most of those points were for comfort alone. Soundwise I would have ranked them about 10th. I've since sent these back in favor of my overall winner, the AKG Q701 after removing the bass port sticker/governor. Makes it hard to listen to anything else.

Pros: Extremely comfortable. Memory foam allows for hours of use and comfort.

Great sound out of the box. No sound card necessary.

Sleek design, plastic but it is well constructed. Much better build quality than the HD 201's I have.

Not bass heavy! Clean clear audio in all ranges. If you want a ton of bass don't buy these. If you like a good bass mix that has tight kicks buy these.

Dem punchy bass kicks!!!

Cons: 3 meter chord.

Ads say the headphone jack is remove able. But you can only use Sennheiser's special chords. They lock in after they plug in. I youtube'd this to see what it looks like and how it works.

Other Thoughts: Extremely impressed with the quality, comfort, and sound. Best set of cans I own hands down. The sound quality kicks the snot out of my beats solo hd's.

Pros: extremely comfortable - can be worn all day and not even feel them
good all around sound quality
very long cable

Cons: leaks a lot of sound - what you are listening to can be heard by others around you

Other Thoughts: well worth the price, i recommend any headphones from sennheiser. they are the best headphones i have ever owned