Is there a difference between the OM and Concorde series of cartridge?

The sole difference between OM and Concorde cartridges is the housing and contacts found on the cartridge.  Whereas the OM range requires mounting onto an appropriate headshell, the Concorde range conveniently attaches directly to the tonearm.  There is no difference in sound between the two ranges, within the respective series of cartridge (ie OM Elektro versus Concorde Elektro, etc).