Summary: Make sure you follow the instructions on updating the controller firmware with the headset. It's all included in the packaging. If you don't do it correctly you will get feedback and other audio issues like the first reviewer has.
Pros: This is my second set of a40s. These ones come with the new Xbox one adapter built into the cord. Unlike previous a40 sets the cord connects just under one of the ear cups. Still the most comfortable headset I've ever used. Like most headsets it uses software to simulate surround sound. Very high...
Cons: The EQ presets are mostly worthless, just different settings prioritizing voice/bass etc.
Summary: So comfy. I have a large head and have had no problems. Also, I like that one can go on their website and get custom skins.
Pros: Super comfortable. Sound great for gaming/Teamspeak/Skype... Don't use them for tunes.
Cons: There is not a permanent mute button. One has to hold down a mute button to mute one's mic. Not ideal. If I cared I would care. I could see others caring more than I do- so I feel I should at least mention it. I, on the otherhand, care so little that I will not take an egg away.
Summary: It's an open design so if you need it to be very quiet and isolated (say you have a sleeping child or wife in the same room) you'll want to not crank them too loud.
Pros: I've had multiple headsets of various brands over the years. Siberia SteelSeries Elite, Corsair, Triton, Turtle Beack, Razer . . . . none of them compare or even come close. The sound quality is impeccable. Combined with the Sound Blaster software that came with my mobo I was able to easily tweak...
Cons: If I had to choose a con, it'd be that the mic is only of average quality but that's pretty minor. I'm not recording videos for YouTube with a massive number of followers where voice quality is of great importance. For most people, I think the mic would more than suffice.