While my review sample held up fine over the week that I used it, I was a little concerned that if I tugged really hard on the cord, it might be a problem because the connection to the earphone didn't seem incredibly sturdy. But Nocs does say these earphones are durable, so maybe I'm just being paranoid (when earphones tend to break, it's at the point where the cord connects to the earbud).
Not only are the NS400s aesthetically pleasing, but they also offer very pleasing sound for their price. They're nicely balanced with good clarity and ample but not overdriven bass (that's why I describe them as well-balanced). Like a lot of other earphones and headphones that offer a flatter, natural sound, they're designed to work well with all kinds of music. I ran my usual eclectic mix through them -- everything from John Legend to Flo Rida to Wilco and a bit of Foo Fighters -- and came away feeling I'd come back to these earphones after my test run.
It's also worth noting that the microphone performed well -- I got no complaints while I was doing my test calls, and most callers said my voice came through loud and clear.
Overall, the Nocs NS400s are a solid set of earbuds for the money. You have the highly rated Klipsch S4i in this price (it retails for closer to $99) and this model offers sound that's nearly as good but they arguably aren't quite as comfortable to wear. Still, so long as you don't have extra deep ear canals, I have no problem recommending the NS400s.