Originally Posted by
gascostalot
Yes, that's the adapter.
The advantage to this setup is similar to the advantage that moved the market in this direction in the first place; greater flexibility of stem selection for length, angle, and orientation (ie, flipped).
Also, as long as I'm forced to replace the quill/stem combo that came with the bike (as its adjustable stem angle riser wore out and developed play), it seemed like a good time to switch to a more modern setup.