Fluff and Models, Orks are the Comic relief of the Grimdark Universe and GK's are some epic marines that truely stood alone and outside normal Codex Astartes. I started with Space Wolves, because of their fluff, and no one locally played their 3rd ed. codex in 4th. Also at the time i wasn't introduced to Codex DH, and the awesomeness of GK's. The Rebellious Nature of the SW also caught my fancy, as they are Theoretically still a Legion, and one of the few forces that can and will Fight the imperium and not be considered Heretics. CC stories and the heroic saga's that follow GK's and SW have always grabbed my attention, and still do. Although i don't play SW's anymore, they will always have a place in my heart.