How can you pencil out a large square baler over a round baler?

We just got done baling 2700 round bales of straw behind a s660 Deere. Next year the Farm I work for is going from a s660 with a 35’ Draper head to a s680 with a 40’ Draper. we are thinking about going to two tractors, and two 469 balers like the one we have now. Also thought about a large square baler, but how could you ever pencil it out with the cost of the large square baler and big tractor?

How can you pencil out a large square baler over a round baler?