Has anyone used these flies and if so, how'd you do?

Typically the books show them tied on an English worm hook(Mustad 31740?). The latex body is wrapped forward with slight overlap for segmentation, tied down, and some peacock or ostrich is wrapped for the head. An underbody can give the fly some tint of color or you can use magic markers. Just wondering if this style of caddis has worked for anyone, in what shades of colors and in what sizes?

Allan