Most of the operations of any courier take place way beyond our view - our experience is usually limited to the person who collects or delivers our parcel, and our opinion is usually based on whether they manage to get that tricky task right.
Almost like a "good traders" thread, this is a thread for posting experiences of the different couriers.
From that pooled experience, you may get an idea of which couriers are particularly good - they deliver an undamaged package, on time - or bad.
If you've taken the time to read the small print on the insurance exclusions, add that info there too.
Most of us are aware of the intermediaries to use when booking couriers, but I'll add any more to this list.