Ever since I first worked professionally as a character designer for Disney Feature Animation I simply wanted a photoshop brush that would produce a nice line out of it.  Other artists would share their personal brush sets but there were way too many to use and none of them drew their art purely in line.  I looked up to great line artists from the past like Ronald Searle, Hank Ketcham, E.H. Shepard and always wondered if I could produce the same line quality in photoshop.