Abu Ismail al-Ansari: The most knowledgeable person I have ever seen
Abu Abd Allah al-Hakim al-Naysaburi: One of the accepted seekers of knowledge, he traveled in pursuit of hadith, and collected the Sahih, biographies, and chapters with understanding and knowledge, and traveled to Sheikh Abu Bakr al-Ismaili, and narrated more from his peers in Khurasan after hearing him in his country and realizing the reliability of his time
Al-Khatib al-Baghdadi: The Hafiz
Al-Dhahabi: The Imam, the Hafiz, the Mujtahid
Abd al-Rahman ibn Muhammad ibn Mandah al-Isfahani: Praised him greatly
Abd al-Ghaffar al-Farisi: One of the Hadith scholars of his time and a knight of the people of Hadith among his peers