As the name implies, the Bose's IE2 earphones are the second generation of Bose's in-ear headphones. Truth be told, we weren't impressed with the first iteration of this model, which some users complained didn't fit securely in their ears and caused Bose to issue newly designed silicon earpieces to help rectify the problem. But the company has made some tweaks to the design and we generally like the results, though not everything is rosy.
There are actually three versions of Bose's latest in-ear headphones:
Bose IE2 ($99.95): This is the base model, which is a standard pair of in-ear headphones.
Bose MIE2 ($129.95): Identical to the IE2, but adds a built-in microphone for cellphones and VoIP devices.
Bose MIE2i ($129.95): Identical to the MIE2, but with compatibility for iPod/iPhone controls.
Despite the feature differences, the sound--and design--of the earphones themselves are the same for all three models, so they should all exhibit identical sound quality.