S*it can happen to any car with a timing belt at any speed.
It all depends upon the condition of the timing belt and the rollers.
This happened to my wee 944, and what a mess. 11 teeth striped, and
bent valves.....ouch. All I can recommend is to make sure your service
center (or you) change the timing belt every 3 years, or around 40,000Ks.
My service center didn't change the belt because I did very little k's
over the years, and let it slide until age got to it. 5 years is too old
for a belt that costs nothing and yet can cause AUD$5000+.
I know 40,000 sounds too little, but the belt costs almost nothing and
there isn't too much labor involved to upset you too much. Better safe
than sorry.
Otherwise, buy a 911, cos this will never happen!!