They function as expected though they do not always sit as squarely on cubes of block and are a bit heavier than aluminum sideboards. They are durable enough, but they are not consistent in thickness. I bought 16 and have about three different thicknesses between them. The thinner ones are still good, in fact probably weigh a little less than the thicker ones. Only wish I had gotten some shorter as I will need to cut some of them down for smaller cubes, which shouldn't be too hard with a circular saw and a good rip blade. A decent alternative to aluminum initially, hoping to gain in the long run through durability. So far they are a good buy....