Pros Haven't yet tried, but have patients who have
Cons Very expensive
Summary I'm a hearing aid provider and my wife is an audiologist. One of her interns also did a study documenting the potential for hearing damage with earphones.
Tom Merritts abstract is partially correct - if headphones don't block out noise, users typically turn up the volume to possibly damaging sound levels. And, unless you have pretty round, and pretty straight ear canals (most people don't), earphones can be uncomfortable over time.
Custom ear molds with good quality standard earphones may provide excellent quality sound at about half the cost. Custom molds (cost + or - $150) significantly dampen external noise AND present the sound closer to the ear drum, giving you a cleaner sound at a much lower volume. Couple the custom molds with a standard, high quality ear bud ear phone ($40?), and for less than $200, you have great sound - and less chance for ear damage.
OR go first class (for both your ears and your wallet)- we fit patients with custom molds made specifically for Shure earphones (we use Westone Laboratories). First class sound, first class fit - & happy ears. Only drawback is that you'll have to go to your Audiologist or Hearing Aid Provider to have the custom molds fit.
Pros Amazing clarity in dense music, So quiet, when the music stops you can hear your heart beating, drowns out all the stressful noise of traveling effortlessly. Customer Service at Shure is top notch. My fourth pair of headphones. All connects are gold.
Cons Volume adjustment seems cheap, Price (ebay deals can be found new for less than MSRP),
Summary My first Shure headphones were E3C's that I bought with my 5th gen IPOD. A huge upgrade to most headphones, they were basically earplugs with good sounding single driver components. I broke the earbud holder on two pairs of those, since I would sleep with them in when I was in the Navy. Shure replaced them with brand new ones no questions asked and the second time, they gave me E4C's. Which sounded even better.
Well I had those old E4C's for about 2 years now, and I was tired and lost them at work. Some lucky guy found them and I have these now thanks to my girlfriend.
The sound is twice as good. I listened to the newest Radiohead album earlier today (lossless of course) which I've seen live in concert and listened to hundreds of times. With about 2 hours of use on them thus far (no real break in), I heard drums in the last track and people talking during instrumentals that I have never heard before. My Car stereo is a stocker and my home audio equipment isn't as amazing as it could be. I've heard some amazing standard 2 channel home audio systems that were amazingly expensive and detailed. These little headphones will make you feel like your getting a private to yourself taste of that.
I won't tell you the bass sounds amazingly low and robust, it sounds low and precise but it's not thumpy and obviously you can't feel it like a show or big speakers will so that may make some people shy away. I am stoked though, these babies will drown out the annoying people at work and serve me well when flying near screaming kids.
Pros They are perfectly balanced and their handling of both lows and highs is quite excellent! When I took them out of their box, the first thing that hit me was how light they are!. Talk about sound isolation and comfort - unbelievable!!!
Cons Price! They are on the expensive side. However, you have not listened to your mp3 player until you put on these buds!
Summary I like their sound quality, which I found to be superb. Their sound isolation is unbelievable and very comfortable. It's only the price which is going against them...right now I am dreading the moment my wife finds out that I have spent so much money on earbuds!
Pros highs/mids/lows crystal clear, just as clear at full volume, not a hint of distortion! extra comfortable - you can use them for hours, plenty of extra buds for perfect fit. Perfect sound reproduction!
Cons price, but worth every penny. besides, good headphones will last forever!
Summary Shure SE420's are the best I've heard. I originally bought the SE530's and returned them. The cord was too heavy, and the bass was overpowering and distorted. The 420's deliver a perfect mix, from punchy bass notes to crisp highs, for all types of music. You will hear notes in songs you previously never heard before! If the 420's a little too pricey, I highly recommend any of Shure's in ear headphones. Don't waste your money on Bose. Only Shure can produce a sound this clean!
Pros Deep true sound. Fantastic fit. The foam earphone sleeves once you have the correct size are excellent. Not bad to train with and you can fit the iPhone mic accessory.
Cons Expensive but these are the only ones you will ever need.
Summary You read a lot of reviews on earphones and they are really mixed. I have bought a lot, mainly whilst traveling and you seem to able to get them cheap in places like HK. The US is also very good. So I've build a collection. I topped it off with the SE530s and was dissapointed. I'm not an audiophile so can't explain why. I did buy a set of UE Pro 10s and the sound quality was better than the SE530s but the fit was terrible. I was able to return them within the required period to an Apple shop. I have smaller ear canals and I found that the UEs fell out. Realistically earphones are a very personal preference. For me the 420s are perfect. Great fit and very deep rich sound. I'm a classic rock follower. Pink Floyd, Led Zep, Tull etc and maybe the 420s just suit that type of music.