Very good; not great but very good.
I tend to find McEwan's books either Very Good or Not So Good - loved his one about the balloon, the war (Atonement), the frozen Norwegian wastes (I wrote to him about that and he was kind enough to send me a long reply explaining an anomaly)... not so keen on Amsterdam (which I think won him a prize).

Sweet Tooth is funnily enough in Le Carre territory. I thoroughly enjoyed it and it deserves to be in the Booker final six but not a patch on A Delicate Truth which is brilliant.

Just an extra thought from my nights sleeping, dreaming and thinking... the twist at the end is brilliant, sending the quality of the novel from Good to Very Good.