Rauchway's gotten excellent reviews (it might be worth reading a few of them, just to see what the real points of contention are. Avoid the NYT, though: they have a nasty habit [lately, at least] of assigning books with historical and political import to ax-grinding enemies of the authors) and has a very high profile. Never heard of Smiley, but it's not my field.

I was leaning toward the Rauchway book myself, so thanks for the input!

And I think I might just read the NYT review, bearing in mind that whoever wrote it was probably looking for any and everything to pick at!