Currently, Brady is extremely accurate. During his title runs he would often throw late over the middle which resulted in many wayward passes and interceptions. Since then, he has cleaned that habit up. He also instills a certain confidence in his receivers as he is notorious for not hanging them out to dry (many qbs do hang out their receivers).
The thing with Brady's accuracy is that he struggles sometimes throwing accurate passes in the 15-25 yard portions of the field. Furthermore, he is wildly inaccurate when forced out of the pocket or forced left (the same holds true for Peyton) so I cannot grade his accuracy up there with Montana.