Here's how good it was: You knew how it was going to end, but you were still hunched forward so you could reach your nails, the better to gnaw at them, as the movie approached the climax.
Go see it! As Laura pointed out, the movie "earned" its "R" rating because of the scattering of the F-word throughout. If this is more offensive to you than some movies that get "PG-13" ratings but are objectionable in other ways, then you will have missed a great movie. But maybe you can watch the DVD when it comes out, if it comes out in a version where they have changed all the F-words to some other words that are less offensive....
...All of which of course could lead to a rousing discussion of the ridiculosity (yes, it's a word) of the Motion Picture Association of America's ridiculous rating system, if Madame L were at all interested in such a discussion.
But she isn't. So Madame L thanks Laura for checking out the "R" rating and vows to check out movies in the same way for herself in the future.