Check out the rewards you can unlock during the Kalimdor Cup in Patch 10.1.5!
Windborne Velocidrake Scales Color
Windborne Velocidrake: Teal Scales can be purchased from Maztha for 30 Riders of Azeroth badges in Patch 10.1.5 at the Rostrum of Transformation in Valdrakken.
The color has been added to the game in Patch 10.1 but was unavailable until now. You earn the badges by completing Dragonriding courses during the Kalimdor Cup.
You can preview the new scales color here.
Dragonriding Cosmetic Set
Furthermore, you can buy a cosmetic set piece called Drake Racer’s Silks Every piece of armor costs 15 Rides of Azeroth badges. The set is comprised of 7 pieces of armor:
Drake Racer’s Silks