I'll throw my 2 pennies in as well - coming from a 50" panny plasma, I have seen no issues with motion during sports, with or without CMD. I am itching to try out some hockey on it but have not had a chance yet (still I'm temp setup mode while I build the screen frame).
Also no issues on 24p blurays.
I do find myself flipping on CMD 3 sometimes while watching live HDTV sports, though that's probably so I feel satisfied in making out every face in the crowd during a game . I don't particularly like it when watching regular tv content (mainly because the rs45 looks fine to me without it engaged) but it is not the end of the world if I leave it on.