i'd have to agree. This week on 1 account i did 20 Brothers easy, and got 2 Masks...and the other account I did 20 Brothers hard and got 2 Fans, and about 3 Gourds

...so i'd say it's roughly a 10% chance (i think i got about 3-4 epic nature stones on each as well...but i didn't keep track). After they nerfed the gold/epic stones, i'm not as enthusiastic about getting them anymore, lol.

next week i'll try Pain hard for the Sword, but I suspect that'll be the same probability.