After a lot of research, I decided to take the plunge and get the UM3X's by Westone because it seemed like it had the sound signature I was looking for: strong bass, evenly strong mids, slightly softened highs, good separation. Well, I got my UM3X's today. Here's a few first impressions from an amateur listener.
Since I'm going to be doing 90% of my listening on the road, I thought I would use my phone so I could see what I was going to get 90% of the time. All songs were played from my HTC Incredible. Some are 320kbs, some are 192kbs. I listen to all kinds of music except rap, however I picked these 3 songs to listen to first on purpose, as I will explain below.
Song 1: 8Bit by Deadmau5 - This is the first song I play every time I try a new pair of headphones. I use this song first because it's just one of my favorites and I know it the best. For me, I can tell a lot about the sound signature with this song. My first impression? The bass is solid and crisp. It's not lacking anywhere, but this isn't a huge bass song. I wait a little longer for the chorus to kick in so I can get a grasp on where the mids stand. When it does, a smile only comes over my face. The Mids are normal! Oh praise Jesus! =D Coming from the TF10's, this is HUGE. They're not overshadowed by the treble and bass. I continue to listen and enjoy the balance when my first moment of shock happens. At 2:19 in the song, the music cuts out, and for the first time I've ever heard, the music just STOPPED. I don't know if this is called roll off or not, but in every other IEM I've tried, the music sort of faded away. In these, the music was suppose to cut out and CUT out it did. I'm impressed.
Song 2: Faxing Berlin (Original Mix) by Deadmau5 - I play this song next because this is the most bass heavy song I have. It's one of my favorites, but I've had problems with it before, especially at the beginning. With my MEElectronics M6's, the bass is over powering. It's just too much and my ears can't take it. With these, not so. It's strong, it's got punch, but for some reason, it doesn't hurt, it's controlled. By the time the chorus starts to come in and the bass is lessened, I'm normally starting to feel a headache come on. Even in my TF10's. With these, while the bass seemed just as good in every area, it wasn't the case. And then again, when the chorus came in, the mids were more prominent than I was used to, which was nice. =)
Song 3: Yellow, by Coldplay - I play this song third because I've had more problems listening to this song than any other. It was this song that taught me that I was sensitive to sibilance and certain high frequencies. The constant bashing of cymbals is absolutely brutal to me. As always with a new pair of headphones, I go into this song scared, because personally, I don't like feeling a shrill pain. I turn the volume down low and wait for the major whammy to come in like 5 measures in or so and then I realize... hey... I think this might be okay! I slowly turn the volume up and further amazement follows. The cymbals don't hurt! They're kind of annoying, but that's my problem with the song. This is also where I first noticed the amazing instrument separation that everyone was talking about. Its so true! I'm hearing things that I've never heard before! I may have heard them with my TF10's, but the music is just more appearing with these.
I think the only down side I've found so far is that some higher notes hit by the singers is kind of shrill like the cymbals usually are for me. But this is far and few between and I expect it to get better over time. I'm incredibly impressed. I love the fit. I know they'll fit under my helmet and not give me any problems. The separation & clarity is the some of the best I've personally ever heard, the bass is solid, the highs are slightly backed off simply so they don't hurt, and the mids are perfectly balanced with the bass. I think I'm in love.
With other headphones, I had to focus on how great that particular headphone did a certain particular thing well. With these I get to focus on my favorite part: the music.
) These are an incredible pair of IEMs 
The wire is incredible as well. It can take some abuse compared to other IEM wires that easily break. I can afford to be quite careless with these and be confident that it won't break 
