Generally a solid fun film. Urban was great, as was the woman playing Anderson once I'd gotten my head round the fact she was a rookie rather than the more experienced comic character.
The villain was fine (though in terms of a cheap to realise on screen crinimal P.J. Maybe could have filled most of her role easily); and lots and lots of 80's style uber violence that, in the desperate desire for a US PG-13 rating, we rarely get these days.
Other than a brief subplot with some other Judges the entire film is in the trailer (including Ma Ma's ending). If you're pushed for time you could just watch the trailer and all you're missing is lots of violence.
The low budget did show up in a few places (most noticeably that when Dredd's distress call is first answered only two Judges turn up).
It was a bit more serious that the usually bonkers gallows humour of the comic. Something like Dredd arresting the hostage he rescues near the start for some really minor crime would have been more in keeping with the tone.
Still a very solid foundation for future films though.