Abu al-Fath al-Azdi: Trustworthy and truthful, except that he had a bad madhab (school of thought), he was astray, and I have not heard anyone mention him except with good.
Abu Hatim al-Razi: Shaykh (elderly scholar)
Abu Dawud al-Sijistani: Da'if (weak)
Abu Zur'ah al-Razi: Saduq (truthful) in hadith
Ahmad ibn Shu'ayb al-Nasa'i: Not strong
Ibrahim ibn Ishaq al-Harbi: He was a hafiz (one who has memorized the Quran), precise, pious, there was no one like him here.
Ibn Hajar al-'Asqalani: Saduq (truthful) and Hafiz
Al-Daraqutni: Thiqah (trustworthy) and Thabt (firm)
Al-Dhahabi: The Hafiz
Salih ibn Muhammad al-Jazara: Saduq (truthful)
Authors of Tahrir Taqrib al-Tahdhib: Thiqah (trustworthy), Abu Dawud and al-Nasa'i weakened him because he leaned towards the Mu'tazilah during the Mihna (inquisition), and this is not considered a valid criticism.
Yahya ibn Ma'in: There is nothing wrong with him