First, let me say that I aesthetically like most the Cook Bros stem, which has been discontinued by them. It never found its way to popularity and relied on a quill based design that has become far less popular.
My inclination in a non-suspension stem would be the Syncros CattleProd if I needed a quill variety. The materials, design and workmanship is un-equaled for a welded stem.
If I were looking for an Ahead ot Threadless style, the Ringle Zooka or again the Syncros CattleHead. The Zooka as a machined from billet piece is very impressive, well designed and executed. The CattleHead is the Syncros version of an Ahead stem.
Without a doubt the Aluminum SoftRide model.