From an economic point of view the people to ask are Cathay.
They published a background paper that compared the 777 to thier A330s.
There conculsion: the airbus is about 60m USD cheaper but the Boeings are more economic. The cross over occurs at 6 years the the Boeings are cheaper. Airbus's business plan gets you over time but they discount the upfront price.
Interestingly the Cathay average MELs per flight for Airbus aircraft is 10 the average MELs per flight for Boeing are less than 1.
Having said this the economics of one airline pilot and engineering type are huge to small companies but less so to large companies who reach are critical mass of about 24 aircraft.
A start-up company would definately favour the cheap aquisition costs and pilot training simplicity of Airbus.