Is the bezel of the 965 substantially harder than the plastic of the old models? I have a 955 and find it scratches super easily. Even touching a wall very lightly will usually result in a (small) permanent mark.
And does it make real difference in practice is kind of impossible to say. Plastic has usually been enough for me already, so having Titanium would not make much difference, but if you have habit of hitting it to things, then it might be make noticeable difference. But your question was about hardness, not about how the hardness shows in practice.