Joseph Klann provided a useful comparison of the leg designs for the Mondo Spider and Theo Jansen’s Strandbeest at this (archived) link: http://www.mechanicalspider.com/comparison.html.

Here is an excellent web page about the Klann and Jansen leg mechanisms, as well as other leg designs: Dog Feather Designs.

This article compares the leg designs:  Mechanical Spider Using Klann Mechanism

This is a youtube video prepared by William Thielicke that illustrates the two leg mechanisms.