The GSA have a lot more wind protection than my regular GS, I have never ridden one but they are a lot bigger and when I bought my GS I wanted to go smaller at the time. You should ride one and try it out, i believe they may be as good as RT almost?? The RT is a sweet bike!!
When I bought the GS I wanted something a little slower than the RT for when riding with my wife on her spyder. This GS definitely does that and has slowed me down so what, the RT would easily cruise on highway 80-90 no problem all day long and my GS, 70-75 is comfortable not saying I can’t do 80-90 but just more comfortable at 70-75.