Some other means of comparison with quickness:
Sproles 20 yard shuttle 3.96 3 cone 6.96
Vaughn 20 yard shuttle 4.22 3 cone 7.10
Career Production
Sproles 815 carries, 4,979 yards, 45 TDs, 66 receptions, 602 yards, 2 TDs
Vaughn 478 carries, 2,707 yards, 28 TDs, 89 receptions, 976 yards, 6 TDs
Darren Sproles had an incredibly well developed lower half of his body and was also highly, highly disciplined in the weight room even in the later parts of his career which explains his longevity (15 years in the NFL). Would be amazing to see Vaughn be able to translate the same way, but Vaughn and Sproles don't have very similar builds despite what the height/weight would tell you.