What is the opinion of the book "Counsels of Scholars at the Approach of Death" by Abu Sulaiman Al-Raba'i?

The book "Waṣāyā al-ʿUlamāʾ" (Counsels of the Scholars) is a good book in its field. The author began it with the counsels of the prophets, then the Rightly Guided Caliphs and the esteemed Companions, and the scholars of the Salaf. He mentions the chains of narration (isnād) through which he transmitted these counsels, however, weakness is frequent among them, though some authentic ones are also found therein.