I haven't read his books, but I've seen his first book recommended on numerous occasions. As far as I'm aware, his work is generally well regarded.
Dialectical monism has been iterated upon throughout the history of philosophy in numerous, varied forms in both the East and the West.
From Anaximander positing the apeiron (boundless; infinite) as the cosmological constant/origin from which all opposites emerged from and returned to, to the unity of opposites proposed by the 'obscure' and the 'weeping' Heraclitus, the Absolute idealism of the German philosopher G. W. F. Hegel, and even to quantum physics when Niels Bohr proposed the complementarity principle of interpretation. Bohr also adopted the taijitu for his coat of arms when he was knighted by the Danish government with the Latin motto: contraria sunt complementa (opposites are complementary).