Spot the differences?



To my eye, the only visible difference is that the ST has a top nut and the Sachs has a comparable sized spacer.
The weight difference is minimal- surely no more than a couple of ounces, half a pound at worst.
On a ride, I'd be hard pressed to tell the difference in ride/steering quality.
More a fan of the quill stem than the threadless setup from a purely aesthetic viewpoint, but The Industry does direct a certain amount of style/component selection on modern frames.