All in all, it's working well.
1st little problem matching the resolution of my auxiliary screen with that of the host PC. You can't enjoy the maximum resolution (2560 x 1600) on the 2 screens at the same time.
2nd problem: for an additional wireless keyboard with a Logitech key, if the key is plugged into the dock, there are delays and therefore lost characters. You have to plug the key into the host PC.
Apart from that, everything's fine, and Ethernet transfers are very fast.