One of the unexpected byproducts of getting the iPhone is that I'm listening to a lot more music on the go. There are two primary reasons for this. The most important one is that my phone is almost always with me (unlike an iPod). Since the iPhone is much more than a phone, but is my phone, I now almost always have music with me. The second reason is that the experience is just so nice that I really enjoy using it. The integration of the phone and music player into the same device has some nice other benefits, like still being able to receive a call while walking around the city or working out and listening to music, or books, or podcasts. Listening to more music I decided to do an upgrade of the earbuds that come with the iPhone. The included buds are okay, but you can do better. This is a tricky upgrade however. The iPhone comes with the customized headphones that have a mic in them for making phone calls (which is great by the way, it's really nice to do calls with both ears). Of course you can plug in normal headphones and they work fine, but with less functionality.
UltimateBuds came to the rescue with an innovative approach. You can send them your iPhone headphones and they will detach the Apple earbuds and put the Etymotic ER6i earbuds on in there place. The microphone functionality is not affected, since it is still the same headphone set. Brilliant! I opted for this and sent my headphones in a week ago. The turnaround time was fast and the quality of the replacement is great.
I've now been able to try my modified Etymotic ER6's in a variety of conditions and I am very pleased. I'm typing this while using them on a plane and having used noise cancelling headphones as well, these are far superior. The thing that takes some getting used to with the ER6's is that they don't really sit in your ear like typical buds do. They are rather just speakers designed for your ear canal. They go deeper into your and that takes a little getting used to. The sound is great though. Detail comes through crisply, bass is reproduced with depth and boom. Two thumbs up!
My only challenge with them thus far has been on an airplane. I'm a bit more sensitive than most to air pressure and ears. I found that placing the headphones in with a complete "seal" made for a lot of pressure on my ear. Working the earbud around a bit makes it okay though.
If your looking for better sound on the go with your iPhone, and don't want to sacrifice the microphone, this is a great option.