Martin Carthy is an extremely accomplished guitarist, collector and arranger of folk songs and music. His singing is imitated by some, but those who appreciate how talented he is would not even attempt to copy. Beyond that, he is very approachable and is known to take the time to supply extra information about the somgs he sings, even jotting down lyrics for audience members.
Martin Carthy is one of the "Nice guys" in the Traditional Music scene. Do we need any point other than that?
Geoff the Duck!