Picture 9537
I got a chance to mount and use my Garmin mount yesterday and it worked out well.  Being collinear with the rise of the stem works in favor of the Garmin, if the stem were a 17 Degree stem then I’m not so sure if that would work. 
Picture 9538
Nice, clean, and aero positioning.
Picture 9539
From a natural saddle position (riding on the hoods) the screen is directly in front of one’s viewing angle.  The screen’s plane is also close to perpendicular to the line of sight.
Picture 9550
So far it doesn’t vibrate or do anything annoying from riding over unsmooth roads.  I have yet to try to time myself or fumble with the buttons under pressure as that may be a source of problems for a seemingly delicate mount.