Dredd's actually quite a difficult character to translate to film. He's a hero, no doubt, but he's also a merciless and nearly robotic humourless jack-booted enforcer for an unelected totalitarian regime. This was often alluded to in the comics and in the Stallone movie they used the irritating sidekick to highlight that aspect. I hated him but he did serve the purpose in a Jar Jar Binks type way. I suppose it was Dredd's personal integrity that made him a hero. So a classic anti-hero then, but to the nth degree, and without some human weaknesses it's hard to get a movie audience to identify with the character. Maybe that's why Stallone took the helmet off.