In general, the only people who can find an advantage to a single bolt hub, are the ones that own an engine with a single bolt hub. It costs more money to make a mutli bolt hub, and it's not too likely that DA, 3W, ZDZ and Moki all converged on the same costly "bad idea". They did it because it's a well-proven design adopted from full scale practice. Slipping props are not a "good thing". Would you put aluminum bolts on the wheels of your car so you could bounce your car off curbs without bending the axles?

Also, all of the 6 bolt hubs use a 10mm prop shaft designed to fit the props without drilling the center hole (Mejzlik, Menz, Air Models, Fuchs, Engel, MSC, Bolly, AirWild).