Keef, you might find the /MT:n switch a delightful addition to your command line.
Old dog, new tricks. Shows how long since I've read the help page for robocopy ! I do believe that flag is a fairly new feature.
Admittely though, I don't really do much work with robocopy anymore, so I have not had the need to optimise my backup times.
Worth remembering just in case for the future though.
Tip of the hat to you Bushfiva.
P.S. Not that there's anything wrong with robocopy, infact it would be my first choice of tool on Windows. Just because Windows is not a primary OS for me, so backup routines are minimal.