Is Surgery, Advised For 3rd Grade Acl Tear ?

hi met an accident on 5th dec 2010 . My knee swelled up doc recent 8 days rest so that swelling goes down.now swelling is gone i dont have any pain mobilisation is good but mri is showing 3 grade acl tear and marrow contiution, doctor has recommmended 3 weeks physiotherapy if improvement not there then to go with surgery ,i have consulted another doctor he is recommending surgery rightaway what should i do