> I should add that I updated the mirror with the same
> settings today and it took ages... I thought the
> cache would take care of that.

Update depends on the speed of the server and round trip time (ask server has
this file changed and wait for the answer.) I get about 3 files per second.
Size of the files are irrelevant.
On my mirror it takes about 27 hours to update. If it was redownloading it
would take 77 hours with my connection.