Hi Jim,
I have used both types of peacock feather. They both have the same result for me. I seem to get more flies from the packaged than the single feather, but really I've never counted. The trick I use is to spin my tying thread around the peacock before I wrap the hook. This gives me the strength of the thread along with the color of the herl. I use twice the number of herl pieces I normally would before I spin (just like spinning dubbing) then I put the herl around the hook and I have a perfect hook everytime.
Good Luck!
Michael