My first venture with a stock HDquick releasewindshield was with the Dyna Low that I just bought. Picked it up in Milwaukee and rode it to Billings (1,226 miles). Thought it might be a little tall (by about 2") but after reading all this, I might just leave it alone. I'm 5'9" and have a bony a$$, so I don't get much elevation sitting down. Rode most of the way on the stock seat, stopped in Sturgis & bought a Mustang solo that raised me up about an inch. There was little or no buffeting with either seat and vision was bettersitting the Mustang. Gas mileage, however, sucked - barely eeked out 40 mpg, but it's uphill and against the wind all the way.
Can't adjust the QD downward because of the headlight cover and idiot lights in it. May do a little cut out there if I have any sight problems.

 

Here is a detachable windshield you might think about.

http://www.corbin.com/harley/dyna/hdfxdfair.shtml