Answer:
Although I have had good luck with it, and know other photographers who run Magic Lantern without issues, there are no guarantees that it is safe. It says so right on the website. Even though Magic Lantern does not replace the Canon firmware, it does change some settings in the camera
Step-by-step explanation:
The magic lantern used a concave mirror in back of a light source to direct as much of the light as possible through a small rectangular sheet of glass—a "lantern slide"—on which was the image to be projected, and onward into a lens at the front of the apparatus.
The Problem
For example, if you pull out the SD card too quickly after turning off your 600D, you run the risk of bricking it — avoidable, but certainly not reassuring. If you remove the card too early, the camera will freeze and will drain the battery or even cause permanent damage."