My other ANR headset (David Clark Pro-X) broke on one side and during the repair time, I decided to give a try to other headsets and tried several brands including LightSpeed, Sennheiser, and Bose. I came to a conclusion to myself that Bose A20 is the best one hands down of those 3 brands.I bought a used old Sennheiser HMEC 25 series from eBay but for some reason, when I turned on the ANR function, it gave me a loud hissing noise and could not hear my coworker nor ATC clearly. Maybe it might have been broken but on Mar, 2016, they officially announced that they are pulling out of aviation headset business except for Air Traffic Control headset, so I crossed off the German brand from my list.So I bought LightSpeed Zulu PFX for the next try and it worked relatively nice but still had some flaws. Some banging noise on takeoff or landing roll is the most scariest thing from my hearing loss perspective. Plus surprising enough, none of LightSpeed headsets are TSO approved, thus as a Part.121 pilot, it was easy enough to make a decision to return a product during 30-day trial period.Then, I decided to try Bose A20. I should have tried this one first before anything else. Communications are clear and crisp and it does not squeeze my head but still stays on my head steady. Of course I can hear myself loud and clear. The carrying case is compact enough so I can put them in my flight case.The newest version of the A20 has a music features so I can enjoy the streamlines of music as a big bonus if you have a Bluetooth in there. (I believe the old version does not have streamline audio functions in there but the newest one does have it so it came as a surprise, too). When.I make a phone call to a dispatch, I use the Bluetooth with A20. This is far better than using iPhone itself.Overall, it has been pretty great, I probably will be using this for my primary headset even after I received back my David Clark from repair. This is the best headset hands down from my perspective. It is worth every penny and highly recommended.