I think motorway driving is made unsafe by people who do not feel confident driving on them. Removing the speed limit would ensure that only competent safe drivers would use the motorways. Motorways are by definitions roads created to make getting from A to B quicker and there should be no speed restrictions on there, unless at times of emergencies. I believe that most motorway drivers are confident drivers and they should be able to decide the speed at which they wish to travel.
.I think it would be safer to remove speed limits on motorways.