I had read the book, many years ago, so I knew not to expect a fast-moving plot or a totally happy ending. I enjoyed it and thought the screenplay and acting very good. I must return to the book again, and see what they left out.
Of course there are nitpicky things, like Cumberbatch's mother appearing to be only about ten years older than him, but overall it was pretty well done.
There's a film coming out, I think, of McEwan's "On Chesil Beach". That will have to do a lot to win me round, as I found the book disappointing. The whole story hinges on one blundering attempt by newlyweds at having sex; not only will the details of this be hard to film, but I found the consequences
of the blundering stretched my credulity. I will say no more, for the sake of others who might want yo read it or watch it.