As someone already said, in this current market you will get a great value GIV-SP that the boss will love for its room, range and reliability. And the initial savings in capital outlay is a lot of fuel.
With Seletar now at 6000 ft you should get 8+ hours of fuel off on most days to be one stop to Europe or Hawaii (probably 2 to mainland USA) and direct anywhere in Asia or Australia - which (except for mainland USA) is what a GV, G550 or GLEX will do more efficiently and faster.
And Seletar-Dubai should be doable now, it used to be Seletar-Muscat.