Long loading times with very common "stuck at 95%" errors didn't allow me to explore the demo nearly as much as I intended, which was gravely disappointing. But the little I did get to play was fun. Shooting felt satisfying and the flying-hovering combo is easy to do and interchangeable too. Agreed on the boring central hub and the annoying character walking speed there.
I also intend to buy, but probably a bit later with the first of the price drops. I want to make sure I avoid the network pains of the first couple of weeks. Also because I return from 2 weeks holiday in Argentina when it releases and go straight into work, so I'll need time to recover.