Andy, from Total Gaming Addicts, said;
Overall the G635 is a brilliant headset. Its comfortable and sounds superb.
I would, however, have preferred a slightly better microphone, as compared to various mics I use frequently it is the only part that doesnt feel up to the standard of the rest of the headset. The compatibility with multiple devices and conservative design makes the Logitech G635 a serious contender if you are looking for one headset to meet all of your listening needs.
Source: N4G PC Logitech G635 Review