I previously owned a paid of Denon AH-C551 earphones, until the right earbud died (I opened up the unit to see if the problem was fixable, but it was just too fiddly for my liking). I loved my Denons - Despite the top end being a bit unrefined (although this softens as the drivers burn in) - They were great value for money.
However, when they died, I decided that these Shure SE215s were the way to go - And I couldn't be happier at the decision I made. I looked at a great many earphones up to a price of around £130, but plumped for these in the end because they were widely reviewed as having all of Shure's well known qualities (superb build quality, excellent sound isolation, a surprisingly wide soundscape and a pleasant warm tonality), but at a price point well below Shure's top end models.
I can tell you that the reviews do not lie. Despite being single, dynamic driver models, they lack nothing in terms of clarity and separation, either - Which is very impressive given the warm tone and decent bass response given. Incidentally, in terms of the bass - Those of you who are total bass heads probably won't want to invest in these, and would probably be better off going for the (in my opinion horribly unbalanced) Bose or Beats by Dr Dre models. If I had to put the bass response of the Shures on a scale, it would fall at a happy balance between the bass-heavy Bose, and the bass-light Sennheiser in-ears.
In terms of what music they have been tested with - I have listened to a wide range (even wider than usual with the purpose of writing this review). To give but a few examples:
Johnny Cash - Hurt
I happen to love Cash's cover of Nine Inch Nails' classic anyway, but I have to say that this was an eye-opener - You can clearly hear every breath, finger movement on the guitar, and the occasional less-than-clean note played therein. The sheer amount of detail that I had never heard before was astonishing. When the accompaniment kicks in towards the end the track simply soars.
Edward Grieg - Piano Concerto in A Minor
Again, its the clarity and sense of space that are obvious here. The keys on the piano ring out as if it were right in the room with you, and the orchestral accompaniment is clear but never overwhelming as can happen with some dynamic driver based earphones where one frequency sort of "drowns out" the others
Metallica - Call of Ktulu (from S&M)
This is a particularly tricky one as it combines rock and classical music together, which can often get rather muddy (again, especially on dynamic driver earphones). The Shures dealt with the piece extremely well, I feel. The track possibly lacked a slight amount of attack at the top end for the strings to really "sing" over the guitars and drums, but only when compared to multi-driver armature earphones. The clarity was still there, and the bass from the drums and guitars was impressive - Full and powerful without being overly "boomy"
Maroon 5 - Misery
To cover the pop bases I decided to listen to Maroon 5, and the 215s once again excelled here. The vast majority of what we listen to in pop music is squarely in the mid-range, and the detail was superb, and that warm tone was still there.
The fit on these once you get the right sleeves, and you get used to the ear hooks, is exceptional (for me at least). I can happily walk around, get on the train, even run to catch a train just about to leave, without these budging. The fit being so good, of course, means that the sound isolation is second to none, and surely helps with that bass response.
The build quality seems to be exactly the same as the higher priced Shure models I have seen, which is excellent. The high quality detachable cable is, at this price, particularly surprising (given that a replacement cable alone can cost upwards of £30). Its kevlar coating seems to keep it snag and tangle free (one persistent complaint I did have about the Denons), and noise transmission through the cable seems pretty low.
Overall, these are actually better than the Denons I so dearly loved for the past 3 years. I'm still sad to see them gone, but I feel these are more than just a replacement - They are, surprisingly given the price being fairly similar, actually a fairly significant upgrade. If you enjoy a wide range of music and not simply overly-bassy tracks, and want clarity and warmth at the same time, which isn't an easy thing to come by, I would thoroughly recommend these over and above any others I tried, including models from Ultimate-Ears, Sennheiser, Klipsch and Etymotic.