I've been on the same fence several times.
To make a long story short, after numerous test rides on various Road Glides with various windshields, and after owning 2 StreetGlides with several different shields (stock 4", strait 8, 8.5, & 9 inch, clear view 8" recurve, another 8" recurve, and the current 7" HD wind- splitter).
For ME, The batwing provides better protection, and less buffeting than the RG, with all but the stock SG 4" shield.
The RG is much better in headwinds, but much worse in strong cross winds. (more body surface for the wind to push against)
For me to be comfortable on a RG, I would have to have a shield on it that is taller than I want, for reasons of looks, and because I refuse to have to look THROUGH a shield. On any of the RGs I rode, (5 different bikes) if I could see over the shield, I was getting beat to death with buffeting. That includes various flip-up, strait, and even one Klockwerks shield on the various RGs I rode.
I know that lowers help a lot, but because of the temps in my area during riding season, I will not ride a bike with lowers. So that is not a viable solution for me.
For these reasons, I stick with the batwing.
Its also my personal feeling at this point, and I know Ill get flamed for this, but IMHO, the supposed superior handling of the RG comes more from the shape/angle of the handlebars, than it does from the lack of weight on the forks. The lack of weight DOES give the steering a lighter feeling at slow speed, but at normal riding speeds, I think its the shape, angle, and position of the handlebars that make the RG feel more nimble. I recently raised my SG bars up about an inch, and was AMAZED at the difference in handling. All It took was to get the bars in the right place, and it was like a different bike. I think with a straiter, flatter bent bar like the RG has, the handling feel (at speed) would be almost identical.
Just one mans opinion.
FYI, Im six feet tall.