Falcon 50 though best of all business jets, by a mile.
Agree, as one can buy an used* early Falcon 50 for as low as 1.8 million USD and can one stop London from any place in the US **(lower 48) on any day with half way decent weather in London and do it off a 5,000 foot runway, it is hard to beat.
Also it's about the only business jet that I know that one can put eight adult passengers (fill all the seats), baggage, full fuel and still be under or right at MGTOW. Now why anyone would want to have eight passengers in it for six hours or more, beats me.
* They are all used now of course, Dassualt stopped building them, a mistake I think, but what do I know, I'm just a retired pilot.
** I made a few trips from the LA area, to Gander for fuel, then on to Luton in a straight 50. No problem. Even easier in the 50EX, which I saw one of those for sale last week for 8.3 million USD. (Oh, the straight 50 did have the 3-D engines, I'll admit.)