SNS3Guppy, I found a thread in which you or someone else mentioned the QC-15 and would consider it. I overheard a colleague mentioning getting a new headset which was supposedly great but required the purchase of separate mic. I wonder if it was the QC-15? In any case, I recall he had problems with his new headset. I shall have to investigate further.
I find that the setup is excellent, without any problems. I've had clearer, crisper communication than with any headset I've tried before (including the Bose X, which I own, and which I like).
The setup is economical, and its nice when deadheading somewhere or riding commercial to be able to use the headset to listen to a movie or music, or plug in one's personal music player. The u-fly-mic also includes a music adapter, and while it doesn't cut out music, I've had no difficulty at all understanding ATC even with music playing. When in a terminal area or in a location where the radio traffic gets busy, just turn off the music, of course, but it won't interfere, especially if the volume is slightly lowered.
I've found that when using that headset arrangement, I turn the volume down very low, because it's not necessary; I get in the airplane where others have been using a headset like the Airman 750, and the volumes are turned up very high. Cranking that much volume up can cause hearing damage just from listening to the radio; forget the background noises or ambient sounds in flight. That's not good.
When traveling internationally, a headset like the bose works very well when it comes to hearing and understanding foreign accents, poor radio transmissions, etc. One of the worst places for radio work in the world has got to be Pakistan (setting aside much of deeper, darker Africa), and it's not very good in southern Turkey, either. The Bose headset makes understanding weak, garbled, or strained transmissions easier.
Perhaps the best feature of using this sort of headset is that it's very light weight, and it reduces fatigue substantially on a long flight. I do a lot of legs that are seven to ten hours in duration. Some of them are fairly lonely legs, over a lot of water, without a lot of radio traffic. I feel a lot more rested with the Bose headset after a long flight than I do with other kinds of headsets.
I have a significant amount of hearing loss already. Between gunfire and lots of big radial engines, and other loud noises (too much time behind a rivet gun, driving and bucking rivets, I suspect), I hear a ringing in my ears all the time. I miss things the kids say. I don't hear the cell phone. I pass my medical exam handily enough, though with some effort, but I'm missing hearing on various levels, and it shows. I hear the ringing right now, in fact.
I've used headsets that went in one ear only (ala Plantronics T50), big clamping headsets like David Clark (all mine are filled with the Oregon Aero hush kits of high density foam and the wide headbands). I've even worn foam ear plugs under headclamp headsets too. I've worn the Bose X all over the globe. I've worn various helmets, noise cancelling headsets, lightspeeds, etc, and a number of different passive headsets from clamping style (DC, Telex, Flightcom, etc) to lightweight corporate style (Telex 750, etc). All work as intended, but none come close to the Bose, in my opinion.
I don't hear well in one ear; I need to hear with both ears to understand properly. I can cock the Bose off one ear slightly for takeoff and landing, and still hear with both ears and hear cockpit conversations comfortably, or slide the headset over both ears during long, quiet cruise.
The QC-15, if you go that route, uses a single AAA battery, which seems to last about 40-50 hours. A little power monitor light blinks for 10-20 hours before the battery goes flat, and that's more than enough time to preventatively change the battery. I keep several AAA's in my flight bag, and even with a heavy flying schedule at 30-40 days on the road nonstop, I've never gone through all my batteries. If I do, of course, AAA's can be purchased all over the world, and I keep some spares in my suitcase, too.
On that long commercial flight to your next assignment, you might be sitting next to the guy who wants to talk the whole flight. You might not want to talk. Putting on a set of earphones is a great way of throwing up the do-not-disturb sign. People don't bother you. The sound is outstanding, and I can hear things on a little MP3 music player that I can't hear through other means like a stereo player.
In my opinion, purchase of the QC-15 is worth the investment. Purchase of the uflymic is also a wise investment. I figured I'd try it out and see, not expecting much, but have been nothing but impressed. The uflymic comes fully TSO'd (in compliance with a technical standard order), and the seller (a Southwest Airlines pilot: call the company and talk to the owner directly) is easy to deal with, and will explain everything. The company offers a set of earbuds that can be plugged into the uflymic assembly which can be used to bypass the Bose portion of the headset entirely if it fails, and are also TSO'd; these alone meet the fully TSO'd requirement for a headset; I keep the earbuds in my bag as a spare backup, along with one or two of my own Telex 750's, but I haven't had to use them thus far. The headset and mic have been 100% reliable, and in my opinion, better than advertised.