Gary Sinise retains the best of the dialogue and gently adapts the story on either end for cinematic purposes. John Malkovich is credible without being maudlin as Lenny, and Sinise does a fine job as George.
A change I didn't like was the substitution of the Luger for Colt or S&W .38. The Luger gave a dark undertone that American revolvers lack. (That's my biggest "complaint" for this fine film)