I looked at that one. It looks awesome but it's like $1200. They have ones for the Tahoe and Suburban too.
I'm currently looking into modifying one of the many racks available for the 4Runner. Prinsu Designs has beautiful racks in many different sizes for the 4Runner for $600-700.
I was jonesing for that rack before I sold my 4runner. Unless they've changed the design (too lazy to look right now), the crossbars were extruded aluminum, side rails were flat metal and angle brackets were used for mounts. I plan to build something similar for my Tahoe when time allows.