Took me two months, on-and-off, to finish.
It's a great book from a historic standpoint, with it defining a lot of terms that we accept as nothing new today.
From a scientific viewpoint, the theories here are mostly prepositions, for the most part, they lack substantial evidence to back them up. His wrap-up monologue even acknowledges that, and apologizes for not being quite clear on the subject at hand, but it's still one of the most important pieces of psychoanalytic literature there is.