score:5
The book "The Agony and the Ecstasy" by Irving Stone, a biographical novel of Michelangelo, mentions many interactions and conversations by Michelangelo with both da Vinci and Raphael. From the details in the book, it appears that at least with respect to Michelangelo, he was familiar with their works, and they were, with his. The book also recounts the early rivalry between Michelangelo and da Vinci, Michelangelo's frustration and anger at da Vinci's regard of sculpture as an art form inferior to painting, the mellowing of his anger later in life, especially after da Vinci's praise of his work at Sistine Chapel as being close to perfection.