I ran an Alpina on my audax bike for a while, carbon with alu crown and steerer. I would say that clearance no good for anything above a 25c tyre with a mudguard in place, and the fork itself was whippier than I had expected though i am a big fella.
I had a steel one made and it improved the ride no end.
It is still hiding in my workshop somewhere but it has a Chris King crown race on it which has to come off first when I eventually get round to it..