Honestly if you don't have the 10 seconds or less it takes to range and adjust the sight on shots 30 yards and over, you probably shouldn't take the shot anyway, on less than 30 yards it really doesn't matter. If I'm pressed for time onclose shotsI don't have to move it, but I can if things are developing slowly.
I like the precision of being able to dial the sight to a per yard specific setting and shoot dead on. This Mule Deer I shot at 36 yards. It only takes a couple of seconds to dial the sight and for me in my experience is much more accurate than splitting pins and trying to decide whether to hold pin A high or pin B low.
Both systems will work, but for me the Single pinwon out. I like the uncluttered view of only one pin, and being able to set my pin to whatever my rangefinder tells me.
Dan