I have two of those and thought they were nice at first but these sheet does start to tear in the corners. And its not so nice when you have a child that has an accident in one. I prefer these:
http://www.discountschoolsupply.com/...&Brand=&Price=
They come out to a little less than those and are much sturdier. They are easy to put together and there is usually a coupon code to make a little less expensive and free shipping.