I lead a church that opens every Sunday in the school gym. We have two 30ft trailers filled with gear, speakers, truss, lights, chairs, layette etc. Everything on wheels and portable. For a while we used the cheaper hard plastic casters we bought from Home Depot, but they kept falling apart. We're just going to put those roles on something now. We have some that we have been using for over 5 years and they carry very heavy loads every week. They slide through the concert hall and black ceiling and are fantastically shaped and soft enough not to damage a good gym floor inside the building. If you use them for a long time, it's worth the investment.