Read it out of curiosity. It's short, passionate & has a kind of appealing simplicity but also a bit repetitive, & a lot of arguments in it are very vague and shaky. There are some imho somewhat contradictory tendencies in it, probably due to his ambivalence towards both tradition and modernity. On one hand there's an iconoclastic attitude towards 1000+ years of traditional Islamic scholarship, an affirmation of equality & "freedom" among men, and a supposedly contextual reading of the scripture, on the other hand there's dogmatic fanaticism, a chilling degree of acceptance of violence, and a fierce enmity towards anyone who disagree with him. Part of it feels like an evil version of proletarian internationalism.
p.s. It is said that some of his followers in UK & Canada have worked with anti-Israel Trotskyists there, which I find kind of ironic.