I think Rara noodle is closest among noodles to the "authentic" chicken soup based noodle and people who like chicken soup tend to like the taste of Rara. Wai Wai and the likes are more dominated by tomyaam flavor.

I used to like Rara. Just add water, the spice that comes with it and some green chillies. It will taste like one of those chicken soup you get in tibetan restaurants back in Nepal.