I am always a bit dubious watching films of books, even the best ones sometimes change things or add stuff that isn't in the book and that always bothers me.
But, if you haven't read the book in ages and are not obssessive about it (like I am with Lord of the Rings or Harry Potter) then it is easier to just enjoy the film without comparing all the time.
The other week I saw Jane Ayre and it was beautiful. Slow and steady with passsion bubbling under the surface. Tonight I went and saw Tinker, Tailor, Soldier Spy. Again it is slow and quite methodical. It isn't a crash bang thriller but it works because of that. It gives you time to think. And I loved the staging of everything. London in the early 70's forms my earliest memories and the colours and clothes and home furnishing was amazing. So much attention to detail.
Brown and gray, the colours of London!