What are the benefits of using Sai Baba's Udi, or Vibhuti, as described in his life stories?

The Sai Satcharitra describes Sai's Vibhuti (Udi) as a substance of great power and grace. Chapter 35 explains that devotees who apply this sacred ash with love and faith at Sai's feet can attain their heart's desires. The text claims that contact with Udi is potent enough to root out powerful sins and all minor sins, leading to a state of both inner and outer purity. Furthermore, it is said that through the use of Vibhuti, devotees can become fulfilled by attaining the four primary goals of life, including Dharma. The greatness of this practice is well-known among his followers.