"Let's get the obvious out of the way: you can't beat practical effects. When something is real and present in front of actors and the camera, it makes a huge and noticeable difference. Sure, you don't have to "clean up" CGI blood. And you can "save on foam latex" by making your big gruesome monster a digital mass of polygons. But when a creature effect exists in the real world it has a weight and presence that you can feel.
One of the ways that you can bring a creature to life is by sticking a guy in a suit. Sure, it's crude. And sure, sometimes it looks obvious that you just crammed a dude in a trashcan. But when guy-in-a-suit effects are good, they're untouchable. From stalking, snarling aliens to rotting bodies, suspending your disbelief is easy when SFX magicians and stunt folks work their magic."
