I just tried Col-Erase for the first time today on my first homework drawing “Draw The Statue” and just love it. I find it much easier to control than graphite. Producing value scale went like a breeze especially low and mid values. I thought producing darks might be difficult but no, not a problem at all. Just need to press harder. Also I like how it feels in the hand I would describe it as a gliding over the paper surface. I am sure all of this very subjective and everyone should try and see how it suits them. Hope this helps.