The demo looks to be about a third of the map (or more?). Not bad, but somehow doesn't feel like it'll be bigger than Horizon 2. I know it's supposed to be twice the size, but it's just not coming across that way. Maybe it's the fact that the space feels more open this time, and Horizon 2 was more sectioned?
In any case, absolutely loving the demo. I've rerun it three times to try the different cars they offer you, and still can't decide on which one is the most fun.
Just wish they had my control scheme available. I still do not understand any developer that doesn't put in the ability to customize controls. Just let me put e-brake on RB! Well, there is one preset that has that, but it also puts camera controls on the face buttons, so that's useless.