I've just tested RuckZuck and Patch My PC and can't tell you I've been impressed by any of them. RuckZuck failed to find Audacity and Notepad++ updates (there are newer versions of them available), such popular applications... though they both exist in its repository for downloading. It went smooth with updating GOG client in RuckZuck however, Patch My PC couldn't find an available update for it, and it's the same here - this application is on the list. I guess I'll stick to the SUMO and DUMO since I block almost every program in the firewall and look for updates manually, it will fit me better, I guess.