I loved the 2012 Dredd, especially for the way that they switched between the "grungy real world view" and "bright sparkly drugged view" during those sequences. I think that just having the color and image changes in addition to the timeframe shift was a good choice.
Finally a main character who never removes thier helmet/mask actually has an actor play the character with the helmet/mask the entire time instead of removing it to mug to the camera every scene.