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There is a demo on Steam now. Pretty cheeky of them to say it will have stability improvements, since it crashed on me during the tutorial.

Anyway, as for everything else, it's basically the original game, unwieldiness and general jerkiness included. There are no obvious differences, other than the fact that it now has a FOV option and supports wide and ultrawide.

You can't save during the demo, so you'll probably die at some point and then have to restart. Can't see that being a great way to attract new players.