A small downer but there are still:
Why is the NUMLOCK at startup always on?
Password is entered -> Error -> switch off NUMLOCK -> password is entered -> Successful
The annoying somehow only, hence "only" 4 stars.
But perhaps there is some adjustment, with which one can permanently change this.
I have not found any case, otherwise the keyboard deserves 5 stars.
UPDATE 25/12/2012:
Rating raised to 5 stars, because adjustment in the BIOS is present.
Thus, this has been no problem of keyboard ;-)