An anecdote for those who hoped they'd find suggestions in the comments:
I ended up buying some over-the-head earmuff headphones aimed at construction workers (I think with a 25dB noise reduction rating). I put in ear plugs, then the headphones, and play some light music; even relatively loud and nearby conversations drop away pretty quickly. (Ordinary "noise cancelling" headphones aren't intended to block the sound of talking, and don't work as well).
The only issue is comfort; the headphones fit quite tightly. I got used to it after a few hours, and now don't mind it at all. My wife tried it, and couldn't ever adjust.
Noisli — http://www.noisli.com/ is a neat little site for playing ambient noise that I find works great to cut out the sound of talking when I'm using noise cancelling headphones.
At the risk of seeming spammy since I just replied to another person on here, you should check out the Here One by Doppler Labs. I had the first version and it's incredible – albeit mostly a novelty device. They're taking preorders for the new one right now and it seems to no longer be a novelty device at all...
Also since you specifically mentioned comfort, these are just little wireless earbuds that feel comfy enough that you forget you're wearing them, and then you forget how loud the world is when you take them out.
Looks interesting. I have the Bose QC-20s and they're great for traveling. They're great on planes although, as others indicate, they're better at background noise than voices. I held off on noise canceling headphones for ages because I pack pretty light and refused to bring over-the-ear headphones traveling--and then hesitated at the price.
But they were really worth it. I never realized before using them how much I was cranking up the volume to compensate for the background noise even with ear canal phones that isolated relatively well.
I've got the QC-35s. They're actually pretty good at lowering speaking voices to the below intelligible level, IMO. This was also my first pair of noise cancelling headphones ever, and holy shit what a difference they make on an airplane; I'd never really appreciated how loud it was until now.
I also find that I listen to music at lower absolute volume now as a result of the noise cancelling; I'm fairly certain I did some damage to my ears over the years, and at least I'm not continuing it at the same rate now.
I carry Etymotic earplugs with me at all times; they're cheap enough not to worry too much about losing. I also recently got myself a pair of Plantronics Backbeat Pro headphones -- they're great; pretty good at blocking background noise turned off, really good with the noise cancelling on (even in the office) and not nearly as expensive as the Bose headphones. And they sound great both with a wire and on Bluetooth.
I should probably buy some Plantronics stock, shouldn't I? Just a happy consumer :).
I have a couple of pairs of ER20s and some ER20XS for commuting, gigs, noisy places, etc. They do a good enough job that I can go to e.g. a Rammstein gig and not suffer afterwards (tinnitus flareup, headache, etc.)
Noise cancelling doesn't work in an open office, but noise isolation does. I have a pair from https://www.etymotic.com/ . I've tried a couple of different headphones/sets but nothing compares to the products from etymotic.
I used to wear earmuffs at work, eight hours a day. I started to develop intermittent hearing problems (coupled with nasty headache). Like an infection of some sort.
At one point I noticed there's mould in one of the muffs. :(
I ended up buying some over-the-head earmuff headphones aimed at construction workers (I think with a 25dB noise reduction rating). I put in ear plugs, then the headphones, and play some light music; even relatively loud and nearby conversations drop away pretty quickly. (Ordinary "noise cancelling" headphones aren't intended to block the sound of talking, and don't work as well).
The only issue is comfort; the headphones fit quite tightly. I got used to it after a few hours, and now don't mind it at all. My wife tried it, and couldn't ever adjust.