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I personally found Team of Rivals informative, detailed and "intimate". I felt I left it with a better understanding of the interelationships and dynamics of the various personalities with each other and with the times. So much so, that in Lincoln, I could see that David Strathairn's Seward was spot on...
Probably helps that the film was based on the aforementioned book.
I thought Herbert's biography Lincoln was both better written and more factually rigorous.