I like this pattern with a nose cone.
http://reel-time.com/pattern/Rogers/bunny/bunny.asp
I like to fish it falling through the bait and the cone version helps me "stay connected' to the fly as it drops. I think the fast movers like to use thier speed to overtake thier prey and a slow/no retrieve morsel is easy to line up on and nail. This retrieve also keeps you in the strike zone longer. To max "strike zone" time I like to fish an intermediate tipped floating line from SA. It doesn't require that you fish it back to the head so it is easier to water haul and get back to fishing that much quicker.
Jenks