Pros: Comfort
Quality of construction
Quality of sound.

Cons: bulky, but only for transporting. When you wear them they feel good.

Other Thoughts: Do not buy these to use on a PC soundcard. The minimal to letting these shine is to use on your Stereo/HT Receiver or get a cheap headphone amp or DAC... Most sound cards will not be good enough for these.

Pros: Great sound quality, music, games and movies sound clear with a great amount of bass to match, the main reason I love Sennheiser sound products.

Cons: they become uncomfortable after an hour of having them on, they make my ears hurt. There is a plastic piece within the ear cup that adds pressure to my ears, if that part wasn't there it would have been ok, im not sure what the inner mold was for. :(

Other Thoughts: Been trying to find replacement headphones for my computer entertainment use with movies, games and music, I had some Sennheiser HD212 which lasted me 6yrs but recently died which had been my fav headphones, low price and great sounds quality, not to mention the cable pops out the ear cups making them easy to replace. Will keep these HD555 for backup but already looking for a different pair.

Pros: VERY CLEAR! when I play Counter Strike I get accused of wall hacking with these. First time I heard a voice coming from these I looked behind me and these are the 555 sure, but there is a huge sticker on the inside that covers of the most air holes to dum them down and on the 595 they just removed the sticker to add $100 extra dollars to the price but these headphones don't touch your ears at all the are put around your ears so no discomfort so you can Play games with these when hours of playing turns into days playing

Cons: This con is personal I bought these to be my computer headsets but there headphones and now having them I'm satisfied to keep them as my computer headphones

Other Thoughts: These are headphones NOT headsets, the different is that HEADPHONES are for ipods and other listening devices and computers of course. HEADSETS are for computers were you plug in a Usb for extra power to the headset so they can be louder and more bass

Pros: Sounds great for late-night movies, music, or video games.

Cons: Open design, sounds will escape the headphones. But that's not a flaw, just part of the design.

Pros: These are the second pair of HD 555s I've owned. Very durable unless your planning to accidentally trip on the wire and rip the wire out AND break the headphone jack along with your sound card jack. To continue, the quality of sound is awesome. The cushion/padding is very comfortable, so prolonged use is not a problem. Easy to take apart for what ever reasons. Of course, there is the "break-in" period, but, it took me a few weeks to do so b/c of constant use. Everyone is envious of the pair I have, so I'm constantly bickered about letting someone borrow them. That can be both a Pro or con. To keep this simple, the headphones are a good buy. Never more satisfied.

Cons: Extremely long wire. I, personally, don't need 10 feet of wire. Also, the adapter for the headphone jack is pretty large. So maybe buying a different adapter along with these will help.

Other Thoughts: Fast Shipping, ordered on a Saturday night, there on a Tuesday morning.

Pros: Absolutely Beautiful reproduction of sound, amazing clarity, everything is heard, all the way down the a minor drum tap I normally didn't hear in a popular boston song.

Cons: Not 150 ohms, its actually only 50ohm, but even then sounds amazing.

Other Thoughts: Couple this with a HT Omega Claro Halo sound card (here on newegg) and set it to its high powered mode (more then 32ohm-600ohm) and the sound comes alive, its an (expletive deleted) in my ears.

Pros: Comfortable, great sound quality, sturdy.

Cons: Price?

Other Thoughts: Are not isolated at all; your sound can be heard from the outside world and the outside sound can be heard within your headphones to a large degree.

Pros: Covers my whole ear!

Cons: The cable is so long.

Pros: Quality construction
Quality sound
Long cord (depends on person for that)
Price:performance ratio is best for Sennheiser besides maybe HD 280
Padding is incredibly comfortable even after 6 hours

Cons: Slightly aggravating to use the 6.3mm-->3.5mm adapter
People next to you can clearly hear what you hear but then thats the nature of these types of headphones

Other Thoughts: The padding sold me on the headset as I had a pair of cheap Koss SB-45 which gave me a migraine after 30 minutes
Alot of "audiophiles" will drone on and on about these but in the end most of us just listen to mp3 anyway so unless you are a professional musician or are the type of person who really needs to beat the Jones family, just get what is comfortable
If the cord is too long try using a twisty-tie?
My idiot friend sold me these for 20$ and a hamburger

Pros: These are the best cans you can get for less than 300 dollars, seriously (I know they aren't even half that). They have the same drivers has the HD595 and a very simple mod can make them the same (theres just a strip of foam behind the drivers that muffle the sound a tad compared to the 595s). I used HD212 Pros for 7 years and love those headphones to death, the sound quality from these are far superior though and you will notice it right away. Can't wait to see how they sound after 500 hours (headphones need to be broken in). They are also MUCH more comfortable, like pillows on your head. You won't regret buying these.

Cons: This isn't much of a con because it's expected with open headphones but I'll reiterate it for those of you who haven't owned this kind of headphones before : They are loud on the outside if you're blasting music, you don't want to sit in a quiet place listening to metal with these on :). I have owned headphones that are a million times more obnoxious but just be warned; its not a defect or a con, its how these cans are designed.

Other Thoughts: MAKE SURE you are running these through a high end sound card such as X-FI titanium or a Xonar, integrated audio (even the HD 24 bit integrated) will not do them justice, nor will an ipod or any of that kind of junk; these are high end headphones and they are meant to be plugged into something with high end output, period.