A lot more wind noise and flutter on the Road King. I recommend RK's for people who are going to keep it under 60mph and want to save a couple bucks and don't care about having music. Obviously, JMO
The King is the way to go. I wear ear plug for wind, road, and tire noise .. don't need speakers blasting .. can always wear ear phones for music if that's your cup of tea ...
Anyway I like both, and i do tour on my King with zero discomfort, but I'm not as old as some. I love taking off the windshield on a warm day and feeling like I'm on a motorcycle again after a long winter of riding with it on. If my hands could be more shielded in sub 45 degree weather I'd have it all.