Shure SE215 vs Bose QuietComfort 25

Bass is emphasized so there is a good bit of thump while staying controlled. Mids are rich, highs avoid sibilance, though they're a bit rolled off.
Soundstage is okay--instruments are separated out enough for them to not sound like they're all coming from the same place, but it's not particularly wide.

The memory foam eartips mold to your ear to provide amazing sound isolation, though there's a bit of a learning curve to using them. You have to press them together before putting them in and then allow them to expand in your ear. Once expanded they will take the shape of your ear and that way provide excellent noise isolation.

The earphones also come with silicon tips which are easier to use than the foam ones and also last longer.

The SE215 earphones have a negative profile, optimized nozzle angle, over-ear fit and memory eartips that ensure the earphones stay in place comfortably regardless of situation. You can even lie on your side with them.

6 types of plugs (silicon/ foam: S/M/L).

SE215 earbuds use tough plastic earpiece shells, have a robust kevlar-reinforced cable, a sturdy Y-splitter that's difficult to bend and an L-shaped plug that adds additional strain relief. They won't break if you snag them, drop them or sit on them. They're also completely sweat proof so you can use them while working out without having to worry about damaging them. They're durable enough for professional stage use for which they were specifically designed for.

The SE215's 6.4-ft. cable is very thick, and further reinforced at the left/right split point. Reviews confirm the durability benefits of its heavy-duty design. If it ever does break, the cable is built to detach safely from the earpieces, allowing replacement.

The optimized angle of the earbuds, over-ear fit, and memory ear tips ensure that the earphones stay in place comfortably regardless of situation. These are also sweat-proof, so they're a great option for active use.

Shure provides a warranty against defects in materials or manufacturing for two years.

The traveling case is small and provides room for spare batteries and other components. This makes it pretty portable, for those that can't or don't want to leave their headphones at work.

These headphones use a triple-A battery to power noise canceling. Should it run out of charge, it can easily be replaced.

With the feature switched on, you can really zone in on the music. Noise canceling is very effective at blocking out ambient noise, especially the lower frequencies. On a flight for example, engine noise is drastically reduced, as well as most of the sound from the conversations in your vicinity.

The QC25 feels comfortable even after wearing it for several hours. The pads go over the ear and feel soft, as the ample cushioning is covered with supple and high quality synthetic leather. Aside from the usual headband padding, it also has an inner Alcantara lining that feels really nice on the skin.

You have a number of options as to how you want to use these headphones' active noise canceling feature. You can either have the feature on or off while you are listening to music, or have noise canceling on without audio. This is a nifty feature if you just want to enjoy some peace and quiet when in a noisy place.

These headphones will not tire your head or neck out, even if you wear them for quite some time. These are pretty light at around 196 grams.

Sub-bass is a bit laid back, but the overall low-end production is punchy and with good extension. Mids are clear and forward so vocals, guitars and keys sound good with these. The upper treble is boosted, which results in good detail, but can also give harshness to the sound.
Overall, this is a really fun set of cans to listen to, especially if you just want to have a fun music listening experience.