I think what you want is a flyable Gulfstream with a good panel...we only do stuff for the AI traffic (computer controlled planes), and our planes (and likely the one you found) are not made to be flown by the user.
Sadly, I know of no good Gulfstream for FS. I seem to remeber that Eaglesoft once mentioned that they tried to do a Gulfstream, but that Gulfstream's legal department did not agree. I heard they are very protective and to not tolerate (payware) models of their planes. But I can really recommend you any of Eaglesoft's models, if you want a good flyable business jet.
I saw their 560, too. Looks great! But I would rather see their Citation X v2 first, propably much more fun to fly.
I think they have way to many projects running in parallel, no wonder it takes them so long to get anything out.