Dredd 3D is a nice follow on from the Expendables. The violence is gory, the dispensing of justice swift and brutal and the weaponary cool. The movie is better than the trailer suggests but not massively so. The 3D was very impressive in a few bits of the film but for the most part I would have preferred it in standard but crisp 2D.
Dredd himself is a cool cat with a firm eye on the law, and he is well played by Karl Urban. As to the mask covering half of the character's face, the creator of Dredd, John Wagner, explains "It sums up the facelessness of justice − justice has no soul. So it isn't necessary for readers to see Dredd's face, and I don't want you to" (Wikipedia).
*** 1/2 (worth your while on an Orange Wednesday)