"I had the Shure E4Cs but upgraded for the bass and am very glad I did."5.0 starson by dkheersink
Pros: True sound, durable construction, several sleeve options for fitting in ear.
Cons: No clip on cord for stability while exercising.
Summary: Like I said, I upgraded to the E5Cs from the E4Cs because I felt I just wasn't getting enough bass out of the 4s. I fly a lot and the ambient bass of planes does reduce the listening experience on the 4s, but the 5s have dual drivers for each ear and you can tell the difference immediately. Bass with the 5s actually thumps and is rich and deep. The trebles and mids are also amazing and incredibly clear (so much so that I'd recommend making as many of your mp3s in at least 196 kbps so that you don't hear as much digitalization) and true to the original recording.
The headphones are heavy, the cords durable, and the construction sturdy. You can tell these were built to last (and should be since I paid $350 for them- you should be able to find them for $350 and not the $499 that most stores charge). My only complaint is that there is no clip included on which to affix the headphones to your shirt to reduce movement while exercising or whatever. This is minor and I just took a clip from another pair of headphones, but I guess Shure doesn't count on many people using these while jogging or whatever. But it sucks to keep having to adjust these every minute or so.
All in all, these are amazing and I'd recommend them whole-heartedly to anyone. They come with a great case and lots of different sleeve types for everyone to get the best fit possible w/o having to go to a professional. I'll be enjoying these for a long time to come.