The Whiting hackles are too small in fibre and have no body in the water. I think they are a poor choice. I like BEP a lot but it is very expensive and you can only get 3 turns on a fly.
I now use and sell two options.
One is a chicken Spey hackle which has fibres long enough, in the largest size, to hackle flies to 5/0. The stuff is not as webby as Schlappen. The fibres actually separate as you are teasing and wrapping and you end up with a nice profile and a good looking fly. The stuff also has no stem so wrapping it is easy. I dye it in a wide variety of colors so you can tie just about any pattern you can imagine.
I am also starting to use Rhea Spey hackle. Rhea is an Ostrich like bird but again the fibres have body and do not go limp in the water. They retain their body and build a nice profile. The fibres on the Rhea are from 4" to 7" long, wow! The Rhea can be soaked and pulled away from the stem allowing you to use both sides of the feather and once stripped the stem is non existent. When stripped the hackle must be counter wrapped for durability. The Rhea is also available in a wide variety of dyed colors in either three packs or by the single feather. A package makes a lot of flies.
One of my favorite new colors is Blue Eared Pheasant, a slate grey with a touch of blue to it.
Email me at email@example.com
for more details or you can touch and feel the materials at River Run Anglers in Carnation.