i end up here at least once every trip to vegas. nothing helps for post drinking munchies or a next day hangover than a big bowl of noodle soup.
two words of warning: their service is extremely slow (and i typically have a healthy tolerance for bad/slow service), and they are not open late on non-weekend nights.
broth was surprisingly deep and flavorful (again, by vegas standards - doesn't hold a candle to viet food in San Jose), and portions are huge.