I've tied a bunch of these lately. From the "Winter" Fly Tyer Magazine.
Fly Tyer Magazine, Fly Tying, Fly Recipes, Fly Patterns, Fly Fishing - The River Knight
They are very realistic. They are easier to tie than it appears. One of the things that made it easier for me was super gluing eyes, etc until I could coat it with epoxy. Head cement made it easier to shape the claws once I clipped out the end of the feather. I also did a little coloring of the foam with a sharpie since it was going to get a coat of epoxy anyway.