I wouldn't worry too much about carbon if you hit the ground. My boyfriend had an aluminum Trek 1200... and demolished it in one wreck. The frame was NOT saveable. It bent in two.
Get the bike you want... if you have a wreck... you will probably have to replace something or the entire bike, no matter what the frame is made of.
Good luck and enjoy riding!
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather, to skid in broadside thoroughly used-up, totally worn out, and loudly proclaiming: WOW WHAT A RIDE!!!!"