i have both the white and sky blue silks. as i did a LOT of digging and really enjoyed the hot and cold game as they had in FF9, these two made for more fun things to do in game, plus made me able to farm a lot of my own materials for lvling up crafting. yeah i passed on the speed one as your chocobo can get faster participating in races, and if you hatch one with the better stats by foods you feed it when young.