I'll throw a DC9 into the equation then....
versus me 747.... ( I dont seem to have a Delta 737...)
I think its more a case of the nose being black on the DC9/737, the 747 doesnt have this and therefore the fuselage livery appears to be more blue than black...
They are all nice models though.. (the DC9 could have done with some silver frames..) dont let it put you off... the 747 seems to be getting quite rare...