I love this setup. I use it all the time, especially against the Dungeon Guardian. One way to improve the setup though, is to use 4 teleporters. Put one on the very ends of the skybridge, and put another about 50 blocks away. Put pressure plates on the ones on the edge, and wire the teleporters (the 2 teleporters 50 blocks away) together on each side, so that you do not have to risk taking damage while turning.