With the right prop and 30% the 73" MIGHT hover with a 1.25 Saito. But at full throttle. I have a 1.25 in the 69" and it is a perfect combo. You will need a Saito 1.80. When tuned right it will be economical. Dont believe everthing you hear on the web. The bearings are just like every other Saito has. What would make the bearings more prone to go out more on the 1.80? Also every Saito produced will come with a low end needle 1.5 turns rich. Most people dont know that and waste alot of fuel. ZDZ 40F3A will work for the 73" if you want to go gas.
Adam