I'm also 6'1" and 215lb. I do look huge, but the SG is bigger than my old 07 RS.
Do you mean it feels bigger?
As for the specs, they are about the same weight. The Road star is longer in length and wheelbase and engine size.
I haven't sat on a SG as I am 6'1" and 240lbs, and I need to open up the ergonomics a little on the road star. Looking to add just a bit of "interior room" for myself.
Maybe I should try on a SG to see how they are set up with relation to the bars, floorboards and seat.