I've just passed 5 years of Bose on my ears, with a slightly different view. I can successfully say I have just about exactly 4300 hours of "earphone time" logged since i bought them. I use the A20's with the bluetooth. They are a prong plug in, we work in dusty, dirty, sometimes +35C sometimes -35C enviornment. After 5 years of dropping them, stretching, bending and stepping on them as well as all the needs of a pilot, I can confidently say they're rugged stuff.
Quite a few passengers of ours use the QC or other versions as well, at the pointy end of the airplane they're the most popular I see. I too realized that my initial needs weren't just for the sound but the over-ear comfort being paramount. Secondly, the noise cancelling is big in two ways. As mentioned earlier, it does help (I find) to increase conversation while decreasing engine noises, actively. Similarly, I look bigger picture to say that if I'm in an environment that is even slightly louder than normal for prolonged periods, it's necessary, I could use hearing protection. That, in place of hearing aids and the time/money spent years earlier like many of my soon to retire coworkers are discovering. I realize your needs may not immediately that of mine, but that, I believe is the focal point of any noise cancelling, active or passive (safety and protection over clarity).
Beyond some simple comments of how much I've beat these up, I think it's well worth studying what options are available for warranty. My aviation grade headset got 5 years. At just before the end of warranty I shipped away and was sent back essentially a brand new headset. They'd replaced almost every component. The detailed work list included them touching and inspecting everything. There's no reason for me to get less than 10 years out of these, which are still very competitive in the market today.
My 0.02
