A really great dish. It's available from many Chinese/Pseudo-Chinese restaurants. I used to despise it's various analogues for their plainness. At many restaurants, the noodles and wontons are in a very watery, almost tasteless, slightly yellow broth (without any red vinegar).
Through observing others eating this dish, I discovered the trick. The trick is to add some soy sauce(small ladle full) and chili sauce (half small ladle full). This is usually available at a restaurant at request or on the table. The best chili sauce for this (IMHO) is a lumpy one with real bits of cut up chili and chili seeds in it. This adds to the 'texture' of the soup.