Tilt-rotor
Interleaving
Two serious disadvantages of the Tilt-rotor are its small lifting capability, and its large rate of descent during autorotation. Both of these shortcomings are the result of the configuration's small disk area, which in turn necessitates a high disk loading.
These two disadvantages would not exist on the Interleaving configuration. For an equal stagger, the Interleaving configuration has 4 times the disk area of the comperable Tilt-rotor configuration.
Supporting info;
http://www.unicopter.com/1505.html