The main difference is the maintanance intervals, a ramp and ball type typically needs a re grease at every 6000 mile service, where as the "pukka" Ducati Course type are designed with a strip check and re grease between meetings or every few hundred miles, with ramp only type being a bit longer, so it all depends on how offten you want to be checking it, if you are a road rider then obviously you dont want to be messing every other weekend or once a month.
Hope this helps Steve and I`ll see you at some circuits no doubt.