Pros: Bass depth and body, treble detail, soundstage, clarity
Cons: Recessed midrange, a little hollow, a little boomy
Really liking these so far. The LEs are not quite fully powered by my Nexus 4, but my Samsung Infuse with Voodoo Sound does them justice well below full volume. The soundstage is really impressive for a closed can, it seems almost as big as my friend's DT880s, albeit not quite as deep and natural; however the vocals are not as noticeably recessed as the 880/990 which seem to place vocals further from the listener as an artifact of having more depth.
Big, dynamic, but clear sound, no portion of the spectrum noticeably colors the rest. The midrange is mostly neutral but does have a little bit of that "Hifi sheen" that makes vocals sound just a tad bright, but not so much that it compromises its accuracy or hinders detail. The bass has a boomy quality to it, seems like around 100 hz, which looks consistent with DT770 graphs. It doesn't particularly bother me, and with a little EQ in the upper lows and lower mids (250-500hz range) it seems less out of place, but it can be a bit distracting just depending on the type of music: these phones sound great with classical, but the bass just seems a little out of place sometimes. The treble can be a touch splashy/muddy, and covers some of the midrange in espcially busy tracks (think more complex psytrance like Infected Mushroom, Shpongle, some orchestral music), but it definitely isn't piercing or sibilant, which surprises me considering its overall emphasized quantity. The soundstage is larger than any closed headphone I've heard, and actually in some cases will throw cues that seem more distant than my HD558, albeit not in as natural a fashion.
For $250 I am satisfied, especially considering they can be driven well without an amp. They sound nice and detailed, albeit a bit more treble-tilted and not quite fully powered judging by the slightly hollow quality to the bass, out of my ELE EL-D01 USB DAC with no amp, but sound very full and dynamic from the HiFiMeDIY Sabre DAC + E11 combo. The warmth from the E11 makes it sound a tad bloated in the bass at times, but nothing to complain about. My Samsung Infuse with Voodoo Sound drives them well for a portable, better than the ELE in terms of power, but not quite as well as the Sabre + E11 combo, as the Infuse retains just a little bit of the same bass hollowness as with the ELE, albeit to a lesser extent. The sound from the infuse has slightly more upper midrange presence than either the Sabre or ELE, making it better for vocals.
Overall I am very satisfied with the LEs: they are my go-to option when I want to be on the go and still have top-notch sound; I prefer the SM3 for relaxing or writing at my local coffee shop, just because of IEM isolation and the more relaxed signature (the DT770s beg you to listen actively; the SM3 is immersive but not overly analytical), but they are fragile and so I forgo them in favor of the LEs or my SE215 for actual on-the-go listening. They also do great for gaming: I use them for Star Wars: The Old Republic and they do everything I want. Positioning is good for hearing where enemies are firing on me from, and the sense of large but closed space that they create is really fitting for a lot of the caves, buildings, and other large indoor settings encountered in SWTOR.
I have recommended the LEs to a few friends who were not even interested in hifi before, just because I think they are a better all-rounder than the other DT770 80 ohm, and I see them as being a big enough leap in SQ over "normal" headphones that even a total newb would be impressed, despite the tonality and presentation being so different from what most people are used to. I don't think they are for everyone, but if you like an accurate, neutral tonality with a V-shaped response, these make a great closed can with no serious faults that I have found. The bass is not quite as tight and controlled as I would like IDEALLY (the DT880 does a better job in this regard), but it's hard for me to consider that a serious fault as most people prefer a bit of extra bass, and aren't used to super-tight, detailed hifi bass anyways. All in all, it's an easy phone to recommend: between the overall solid SQ, enhanced bass, crisp and detailed treble, shorter-but-not-too-short (5') cable, good isolation, easy-to-drive 32 ohm impedance without sacrificing the ability to scale with an amp, sturdy design, and user-friendliness coupled with a hifi sound that remains accessible, it beats out everything else I've seen for a do-it-all headphone, and should be a popular recommendation for budding audiophiles and everyday listeners alike.