Seems like you have already had the debate and made the decision for full length. Many found the other opinions stated in the thread "substantive and well reasoned" also
IMO the perfect UQ covers you well from the shoulders to feet with a couple inches to spare. Do you really need another 1'x4' of quilt to cover the back of your head?
In temps below freezing you should have a backup plan to the UQ. Too many people buy a full length then leave the pads at home to save weight.
The forums have grown since 2009 and most of us fall into the category of car campers or go on weekend hikes that have the option of walking out. Any setup will work for this style of hanging. I would bet that the few that have time for the extended hike into the woods have chosen the shorter quilt with a good pad.