My last bike was a Road King but my current one is a Street GLide. I like them both but I like the looks of the SG just a bit more, probably because I had the RK for 10 years.
I ride a Street Glide. I liked the idea of having a full fairing and tunes for the road, liked the sportier look of the lowered rearend, and don't care for the chrome bumpers and fender tip lights that come on the other touring bikes. I thought hard about a Road Glide, but didn't like the way the rental bike rode when I tried one out.
When I decided to trade in my 2002 Road King I went to the dealer thinking I'd get a Street Glide because I think they are the sharpest looking bikes of the touring line. I rode all the different touring models. When I rode the 2008 Road King, I felt like I was home so I stuck with the Road King and have been very happy with it