I think the remote bays in Rome are best. Lots of guys standing around talking, paying no attention to you at all, drive down the line and stop where you feel its about right.
Safedock seems to be the most common in major international airports I go to, must say something about it. Aircraft Positioning and Information Systemseems to work well but is left seat only. Safegate looks fancy but is pretty much the same as safedock although never seen one.
No one likes the bars and tubes that I have come across. Both seat docking is better. As long as it gives left/right and distance to go indications I don't think many pilots really care too much what the docking system is.