It's always fun to read/hear "arguments" like "the Triton has the best sounds out of all three, period.". Says who? Based on what criteria? In what style of music? The Triton for example, is useless in "bread & butter" sounds like the Rhodes, or
the Hammond B3.
These workstation keyboards or romplers are made so that they appeal to musicians and producers of ALL genres and styles, and when trying to please everybody there are going to be some misteps.
In terms of features, it's like dan said, Fantom-G looks good on paper. And I would argue that the Fantom series (X?) was always easier to use than Motif, even though I never had any troubles with Yamaha. In terms of sounds...I mean I'm basing my opinion on just the early demos, but to ME the Fantom-G sounds EXACTLY the same as the Fantom-X or even OLDER models...
That said... someone mentioned that you're gonna have to edit your sounds heavily because tons of ppl have the same synth. So in ESSENCE - both the XS and apparently the G are BEASTS, they are what you get out of them creatively. If you just buy one of these, and use the presets for a little bit of (poor) playin', then you're just scratching the surface.
Joe Zawinul (r.i.p.) used to have a Korg M1 in his live setup all the way up to until he passed. And he always sounded fresh and personal on what is a really dated keyboard.