Are the Shures comfortable enough or extended use?

Personally, I don't understand the malevolence some people have against Bose products. I've got a number of Bose components in my house, and I find them all to be excellent. Maybe I'm just not discriminating enough, but I'm pretty picky about the sounds I listen to, and my dad was a professional audio engineer; so I don't think I'm completely clueless when it comes to audio products. I grant, however, that I'm not a died-in-the-wool audiophile, in the truest sense.

That said, I have QC2s. The QC3s use the same technology, but are on-ear, as opposed to over-ear. Personally, I think they're outstanding. They're better than any pair of Sennheisers or Sonys I have had. I have not tried the Shure in-ear monitors that Roff recommends. I've read positive reviews of them, and I don't doubt they're excellent. (For the price, they should be.) However, the big problem I have with in-ear phones in general is that the fit and seal of the tips has to be dead on, or the sound will be poor. Finding the right tip is only half the issue. Even with the right tip, sweat or motion can cause them to shift out of position and have to be reinserted or positioned. In contrast, over-ear and on-ear headphones always keep the transducers positioned correctly relative to the ear, so they always sound the way they should. I wouldn't want to be without my ear buds, but to me they're no substitute for a good, traditional over-ear phone.

My QC2s actually died recently, and Bose has been good enough to let me trade them in for a pair of the QC15s, for 1/3 the price of retail. They're on order, so I haven't received them yet. When I tried a pair on at Best Buy, I was blown away by the noise cancelling - much better than the QC2s in that regard. I hope the sound is as good as on the QC2s.

In terms of Bose, I have always found their headphones to be too much of a mass market compromise for my liking - they excel in the mid range that is most noticeable, but don't have the same frequency range.

It could be I don't know what I'm missing. Although the QC phones are in the $300 range, my understanding is the sonic component is the same as their AE2 phones that go for around $150; the rest of the cost is for the noise-canceling technology. And that's right in line with my other headphones. So really, I've never stepped up to something in the $500 range, to say nothing of thousands of dollars. Perhaps ignorance is bliss. At any rate, I've been pleased with them. Since my QC2s died, I've been using my Sennheiser HD 570s, and I find myself missing the Bose.

I ended up purchasing the Bowers and Wilkins P5...but wow am I glad that I did get the QC's.

Sorry if I'm dense, but I'm not sure I'm understanding you: did you go with the Bowers and Wilkins, or the Bose?

EDIT: After re-reading your post, I'm thinking the "QC" reference was just a typo. Those Bowers and Wilkins look like they're worth checking out. If Bose weren't sending me the QC15s for $100, I might expand my search and audition other options. Having said that, the Sennheiser HD 570s still sound great, and are probably the most comfortable headphones I've yet worn - if a bit big and silly looking for public use.