I've only been using it for about two weeks. No problems so far. When I feed him a live mouse, I place a strip of cardboard down in his enclosure over the substrate when he eats. I can hold the mouse by the tail until the snake gets to the area, then I let go of the mouse. He usually strikes right away. After he eats and moves to his hide, I remove the cardboard. He's never eaten the substrate, so I can't comment on accidental ingestion.