It would have to be the Global. Far more of the type around in Europe. Also helps if you are a Captain.
I used to be G5/550 rated and with time on type. I couldn't get the slightest interest until my LPC had expired. On inquiring how much it would be for a renewal from the one and only provider in the UK, I was quoted US55000(!!)
Needless to say, after 15 months in the doldrums I am now doing something else.
The other useful rating in Europe is the Embraer Legacy. Lots of those around.
The Gulfstream is a great aircraft to fly if a tad skittish and not terribly reliable when used like an airliner but a fairly useless type rating in Europe in my experience.
Good luck.