Having made several of these myself for about a 1/4 of the price, I was extremely skeptical at paying the price and getting something better.  However, the adjustments to bring this consistently level with the table top are almost worth the extra.  Having a small piece of wood jam against the lip where this meets the table because it is not perfectly aligned is at best frustrating and potentially dangerous.  This aligns quickly and easily and lasts.  It could be cheaper!