Depends on the silkies and what kind of hypermelanism they have.
Some have Black connective tissues only, skin, tendons, cartilage, etc. This is Fibromelanosis.
Others have everything in black. This is called Leukomelanosis. (black blood)
Pea and Rose combs are both usually dominant over straight combs.
Rose comb X Pea Comb (Wyandotte X EE) will make some CUSHION combs (I like cushion combs)
Leg feathering seems to be dominant, in that a fully feathered leg bird bred to a clean legged bird will produce SOME leg feathering in ALL...