I always loved this purple replicators the most as it showed that they were eating the Asgard metal materials. Somehow the rusty or the humanoid versions never impressed me as much as these ones. I always got goosebumps when I can hear their chearping sound effect and then O'Neill's face expresion then the music together. What a scene! I am not surprised this one was voted the best of season 3.
When you watch the werkfilm it mentions that the O shape corridors were used in Urgo as well, because that was test footage / test episode for the Nemesis. So when they are running on the wall actually they filmed it with white set and the whole background is also digitally painted. If I know it well as I have seen this extra years ago.