When it comes to dry fly hackle, there is nothing better than Whiting Farms hackles, period.
Because of how Whiting gades their pelts and capes, it doesn't matter the grade, the feathers are all the same high quality. Whiting grades their pelts and capes based off of the amount of flies it can tie, which is typically several hundred flies (sometimes more), even on their lowest grade.
Each individual feather is uniform in size, they all have high barb density and each feather is capable of tying several flies. The color spectrums of the feathers, particularly the naturals, is phenomenal. Which is also one reason why there are a lot of "hackle junkies" and collectors, myself included...