The absolute best marabou if you tie a lot of Wolly Bugger and Booby flies. A very dense fibrous marabou that gives a lot of life and movement to your fly.
Choose the right Wapsi Marabou for what you should tie:
Wapsi Marabou = long fibers with relatively hard trunk
Wapsi Wolly Bugger Marabou = short fibers with soft trunk
Wapsi Marabou Strung = long fibers with soft trunk