It seems like this is why they have the clause that you quoted. They aren't yet comfortable guaranteeing reliability or backwards compatibility (i.e. what "beta

It seems like this is why they have the clause that you quoted. They aren't yet comfortable guaranteeing reliability or backwards compatibility (i.e. what "beta" means). If these things are crucially important to you, there's a pretty good chance you shouldn't be using it for your "valuable data".