So, as many of you know Xur brings a pair of Sparrow drives with him every weekend that anyone can purchase for twenty three strange coins. These wondrous hunks of machinery change the boost trail of an equipped rare (blue) Sparrow from the standard orange to blue, green, purple or red upon use (it also ranks them up to Legendary). So, which one do you like to see? Personally I prefer the red trail created by the Stealth Drive. EDIT: Apparently people like green.