Cool. Is the Essential from the X-Factor era with Cyclops and Jean Grey or the later era with Havok? I read some X-Factor in the 90's, but it mostly was in relation to crossovers of the X-Men events like Fatal Attractions where Magneto returned.
Halcyon sounds like a cool concept, what publisher is that?
Essential X-Factor covers the Cyclops\Jean Grey era. The Havok era is covered in "X-Factor Visionaries: Peter David," and they are in color. Halcyon is an image book written by Marc Guggenheim and Tara Butters. I picked up because it came highly recommended by a friend, but I haven't had a chance to read it yet. I don't know if it's an ongoing series or not.