Well Achewood isn't well drawn but it's clean and functional and you can tell all the characters apart, if not from the visuals from the style of speaking. It's just that Achewood has this novelistic character development combined with surrealism (which I think is the most challenging thing to write) and just great dialogue. I haven't seen a webcomic come close. I had heard good things about Diesel Sweeties but it was only ok, and Penny Arcade greatly disappointed, to me it was predictable. I like Ctrl-Alt Delete so far, and Read Meat looks pretty good, but besides that I can't find much that even comes close to Achewood.