Ignition box needed with EFI?

any EFI system worth its weight in gold (as most cost that much) will have ignition built in to control advance, retard and various other things....its cheap to implement and almost needed in a SEFI (none of you TBI boys have that) as cam and crank timing are already a known value. Megasquirt had spark added (MSnS) as only a minor hardware and firmware update.
So I do not need the oem ECU then?