Just to add some comments to this don`t run away with the idea that 5-10% failure rate is small.
In manufacturing terms that is a massive problem. Just think what that would mean if it was total brake failure.
This is the reason i did`nt buy a Porsche. They are getting cheap for a reason.
Sink 15K into an old air cooled model......now yer talking...........if you can avoid the rust ....