I have seen some people buying metal glides wanting to get something more durable than the plastic glides. The plastic glides are softer than metal glides and as such wear down much more quickly. Before you chose to buy metal glides make sure you have considered all the variables. There is a much smaller selection of metal glide so it is more difficult to get the right size for the right furniture. You cannot use metal glides on all kinds of carpeting. On low pile commercial carpeting metal glides are great, they glide better than cheap plastic glides and they are much more durable. HOWEVER, there are a few caveats before you decide on getting metal glides. Most of them are steel glides and will rust very quickly if the carpet gets wet or if they are in a high humidity environment. That being said, metal glides should not be used in a restaurant unless the carpet is rust colored. You can get some that are made of stainless steel but they are much more expensive and typically not available at a local hardware store. NEVER ever use metal glides for any other surface even ceramic as they will mark and scratch your floors with the very first slide. The other issue with metal glides is that they are notoriously prone to rip through carpeting once they use through the thin metal base. To make sure this doesn’t happen to you inspect the glides in high traffic areas regularly and replace them if they are no longer perfectly smooth.