How does the availability of detailed Guru biographies in Maharashtra compare to other works, according to the source?

According to the preface in Chapter 0, there is a scarcity of ancient, detailed, and comprehensive poetic works in Maharashtra suitable for devotional readings like Parayans and Saptahs. The text specifically highlights only two such major works. The first is the 'Brihat or Thorale Guru Charitra' by Shri Saraswati Gangadhar about Shri Narsimha Saraswati Maharaj. The second is the more recent 'Shri Sai Satcharita' by Annasaheb Dabholkar about Shri Sai Baba. The source emphasizes that besides these two Guru biographies, no other work of comparable detail is found, making them uniquely valuable for in-depth devotional study.