I agree with number_6’s analysis. Unless one is willing to travel to a country where the price differential between first and business class is small (e.g. less than $1,500), you are better off saving your funds and flying business class. On BA/QF/CX, business class of today is similar to first class of the mid-90’s. And on these airlines, most have business class on the upper deck of a 747 which to me is almost first class. Although business class on the other OW airlines is variable, it is still comfortable. Also, don’t forget the mileage based global explorer ticket. Certain itineraries may be better suited to the GLOB ticket. I believe that any further advice must await the requirements of the traveler.