Nonu was so scared of Brian O'Driscoll in '05 he tried to assassinate him. O'Driscoll has had pure magic in so many ways, Nonu has always been good, and was more physical to start with than BOD, and has had to refine his game to add the other attributes. However, O'Driscoll when he first burst onto the scene, well the pace of that guy, and the intelligence of him, were something special that I don't think we'll ever see the like of again. Both are legends of the game however, and played different position effectively, with inside and outside centre very different roles. So it is hard to compare the two, but I loved watching the BOD God in full flow