I had a beautiful single place Dominator years ago with a 912.
I opted for the dual bearing head with a slider for two reasons;
First, the extra weight of the engine and my body weight (225#).
Second; I fly in Colorado where the d/a is normally well over 7K.
I had 26' blades (altitude compensation) and wanted the extra strength of the dual head.
Also, the dual head has 3 height options in the tower to adjust undersling.
A single has only one hole.
Never once regretted that choice.