Now that a few people have mentioned about the fact that Li Xiao Ran looks older than Wallace Chung in the series, I feel free to contribute my opinion without fear that I will get stoned by the Li Xiao Ran fans.
Before the series came out, I already thought that Li Xiao Ran looked quite older than Wallace in the pictures everyone posted on the series in the Wallace Chung thread. I don't know why, but Li Xiao Ran looked like she aged quite a bit in those pictures, despite her real age being 2 years less than Wallace's. Then, when I actually watched the series, I was relieved to find out the she appeared quite compatible with Wallace in the very beginning of the series. However, toward the middle of the series, after her character was abandoned by MRF and she returned back to her parents' village, she looked old and austere, with that heavy bun at the back of her neck. The fringe did nothing to make her look younger. That schoolmarm heavy bun just aged her a lot. Now, contrary to the majority of the opinions here, I thought her last hairstyle at the very end of the series, the one without the fringe, made her look younger than the bun style did. She still looked like someone in her 30s, but the bun made her look like someone in her 40s.
Wallace Chung just seems to be blessed with young good looks.
It's a fact that most men age better than women. SO UNFAIR! That's why we should all marry men who are older than we are, so we'll still look younger compared to them! But I digress. Going back to Wallace Chung, I think he just needs to play opposite an actress much younger than he is in order for the actress to still look young next to him! I wonder who's the lucky gal playing his female lead in his next series?