Whoops, I forgot about Duke Nukem's co-op. Rewinding a level playthrough isn't that much different from being able to save and load from anywhere, but still a good idea.
But Furry, I wasn't aware of any graphical improvements to Duke other than the widescreen borders. Duke is just the original game running at a higher resolution - just like Doom and Wolfenstein 3D - and it'd look the same if you ran the PC version at the same resolution.