These days I am very much a computer writer - I don't think I'd have the patience to write anything beyond a couple of pages longhand. As far as editing goes, though, I do still print out regularly and use my red pen. That's not to say I don't do a lot of my editing on screen first, but there is something about having a pen in your hand and flicking through pages that engages your brain in a different way. Besides there is something very satisfying about circling, crossing out, drawing arrows and just doodling that is very satisfying. Sometimes too, I lay my pages out so I can track my chronology and physically move pages if necessary.
It's great to have the technology we do, I'm not sure there would be as many wannabe authors out there if we had to go back to longhand writing!