I use fake plants, though I only recently bothered to get them for my newest addition, a ghost mantis. All of my chinese mantises have always just snubed their butts in the direction of plants or sticks. Since I use screen cages, they much prefer to hang out on the mesh than bother with sticks. In fact, I only ever had one chinese mantis that ever once used a stick and that was a female who laid one of her oothecas on it.
My ghost mantis however loves to hide behind the plants and hang on the sticks. I think fake are easier because you don't have to worry about the plants dieing or mess up the humidity in your cage when watering them. It also makes cleaning the cage a breeze and you can wash the plants off if need be.