Wing Sung has its origins in the 1950s (or earlier, as it seems the ancestor of the company is a bookseller which bought an already active pen-maker) but did not appear as a brand until the 1980s. This made it an early… competitor? Does that work in China in the 1950’s?… for Hero, and had the distinction to later be the first Chinese pen company to appear in the Chinese stock market.
It was then gobbled up by Hero, which hung onto it without necessarily offering Wing Sung branded pens, until about 2013. At that point, the name was made available for licensing, and from what I understand there were several private companies which paid Hero (owned by China, remember– there’s still some amount of communism happening there) to produce pens with the name on it. This probably explains the somewhat variable quality of currently available Wing Sungs, which can span “that’s really good for something this price” to “Well, what can you expect for something this cheap?”
The name, it seems, means “Eternal Life”; the source I take this from also offers that “Wing Sung” is Cantonese pronunciation of the characters, suggesting that the company originates in the south part of China.
Models I’ve examined: