Aside from the aesthetics of the two kinds of stems/headsets (the old-fashioned quill stem is far more appealing, in my opinion), for some riders, including this one, the quill stem has one very major advantage. It's easy to make adjustments to handlebar height, even on the fly, in the course of a ride. If you have any kind of back trouble, the perfect setup one day may need to be half an inch higher the next. Threaded headsets make this very easy.