The ones provided on the plane are David Clark Greenies with one earpiece. They can be uncomfortable but not terrible. There are three sets on every plane so you have a few choices. I intend to get my own, but I haven't decided on which kind yet. I'm on the 73 and it's pretty noisy. I have see a lot of variety in the headsets the other guy has had so far.

Bottom line is, you don't need to rush into a purchase if you don't know what you want. The included ones will get you by.