Had these things for a while now, and still use them with almost anything that has a headphone jack attached to it. My phone, my old iPod, my iPad, my pc, my laptop, and they always find a way to sound really wonderful.
I'm not gonna lie and say I'm some headphone guru. I'm not. But i LOVE headphones. Cheap ones, expensive ones, gaming ones...i mess with them all. I've owned grados, senns, sonys, denons, AKG's, Beyers...really could have bought a car with how many headphones I've owned in my lifetime (a house, if you include all the headphones my family and friends pass down to me).
Point being, I've heard alot. Not all good, but most headphones sound good as follows...with the right input, on the right music, listening the right way...etc.
The Shure's sound good on everything. I have yet to plug them into an input that made them sound bad! They just make music...never forcefully, always relaxed and full, without any irritating edge or bite to the sound, yet always giving the impression that you can hear into the mix as deeply as you want. The better the source, the better the music gets. Key word...MUSIC...not headphones...cause they're always good.
I've owned more detailed and resolving headphones. But they're far more finicky, and seem to do some music good, some bad. The Shure's do everything well. All types of music. Ample bass and drive for rock, good sustain and warmth for vocals, and enough detail for piano and jazz.
I have a box in my garage that is filled with headphones. I have exactly two pairs NOT in that box. The first is a pair on Senn 600's, that I hook up occasionally when I feel like breaking out my headphone amp. The second are these, and they're on my ears anytime I'm outside my listening room/office (sometimes, while I'm in there, as well)
Really no complaints can be made about these, for how good they do everything. The only in ears I've heard that were better are the e5's, and they're just to big for me. For the size, and every limitation the size would seem to impose, I've yet to do better than these for the way I like to hear music. I forget they're on most of the time, except when my phone plays a song I haven't heard in a while, and I catch myself hearing something I never heard before...then I smile.
What I won't say is that they're the best for everyone. While I think anyone would like these alot, some people like a more exciting, up front and present sound, so those people can probably do better. But, for me, they've been glorious!