I am a fairly new user but struggled terribly with the oem and cut down oem for 3500 miles and bit the bullet on the Desierto. Overall I like it a lot but was so used to the cut down shields that it is visually cumbersome from the seat just yet with about 1000 miles with it.
Realizing you are looking for long time users my thoughts may not be pertinent but I am basically the same body characteristics as you listed.
If not for the wind wearing me down with my XD-3 and working me so hard on the typical 250 mile ride to trail I would have been fine with the cut down shield. That being said this Desierto has made riding to the trail a pleasure again.
I leave it in the lowest setting with a slight tilt forward and it works real well. Wind and rain protection is completely satisfactory and it really is out of the way with the trail riding positions while standing forward.The wind noise has been noticeably reduced (always with the shield up on the xd) and no need for Advil to alleviate a sore neck after a full couple days riding.
Pricey but effective is my opinion.
If I didnt have a 12GS as well I may not even have realized that the 800 falls short with wind protection but the bike is too much fun to give up on just for the cost of a rider appropriate shield.