i use racks for all my snakes now too and they haven't had any trouble shedding. i move the water dish to the side that is heated and mist the enclosure twice a day or so whenever one of my snakes starts going into shed. i think that the holes that are drilled into the rubbermaid are actually a really good surface for them to rub their noses on to start the shed if neccessary but i haven't ever seen one of my snakes use them that way. i don't think they always need something to rub on--i watched one of my snakes shed pretty much from start to finish about a week ago and it was really quite amazing. he didn't rub on anything--he just kind of inched his way out of his old skin.