Yeah, I used GUI emacs on and off for more than a decade, most recently — for a couple of months as a primary editor and email client. Emacs with gcc+pgtk patches feels great. Unfortunatley, due to scrolling and, most importantly, C-x/C-c vs cua-bindings (which was non-issue on OS X ⌘ but is an issue in X11 and Wayland) I never feel myself completely comfortable using emacs.