Put it this way: If this special were anything like the cutaways where something is reenacted EXACTLY the way it was originally, only with Family Guy characters taking their places (I'm mainly thinking of the Liar, Liar recreation, Stewie's "Twelve", the Paula Abdul music video, etc.), I would've hated it. This special wasn't anything like that. Even though they acted out the same scenes from the movie, there were more than enough dialog changes and twists to famous moments that it didn't feel like a lazy, frame-for-frame copy.
That said, I do agree that the Robot Chicken special had more variety to it, and because it didn't follow the movie like the FG special did, you didn't know what to expect next.