Argon 18 has built a reputation for building well-engineered bikes that combine light weight with excellent ride quality and clever design touches. The 2019 Argon 18 Gallium has the latest iteration of its 3D headset system, where interlocking solid parts extend the effective head-tube height to get the perfect fit. Argon 18 claims that the 3D system keeps the stiffness in the head tube compared to standard spacers, which can leave room for flex.