Unfortunately, I didn't really purchase these for the noise cancelling. I use them as a flat sounding headphone for doing musical recording and mixing. You will get some bleed from outside noise with these.
If the headphone's insulation fits around your ear, not over it, it provides excellent noise reduction, but not cancellation like the Bose headphones. And besides, airplane rides are usually pretty quiet. Comfort shouldn't be a problem if you make the speaker columns longer for extended listening times. I went on a 5 hour road trip with these, and they never got uncomfortable.
I like them because they are very comfortable and the sound quality is very good with my Kindle fire and iPhone. I have used them on a train going back and forth to work and they do a good job of blocking out the noise.