Agreed - but then a DC-3 is a similar classic -
the B-52's are not used to land the president in front of the worlds press - it will look VERY old - they may well be the last two flying
Don't understand the 4 engine argument any more
and the maintenance costs will be ..... high
As it has to be FlyAmerica I'd have thought a 777 was a good bet - with newer, miniaturised electronics cp a 747 and they'll be building those for quite a while so you can go for an upgrade later.