I think that site has been linked a few times.
Have had Titanium based parts sheer, and countless failures with Aluminium.
The thing that makes me nervous of Carbon is damage.
The whole idea of a mountain bike, for me, is a resilient go anywhere bike.
Carbon needs too much care for my needs.
I throw bikes around, and tend to fall off things on them regularly.
Saying that I use it; sparingly!