Who to Start RB Flex

So luckily i was able to pay attention to the alerts and i was able to pick up Spencer Ware. But i just don’t know who i want to start. Should i start Spencer Ware vs Oak or Gus Edwards vs Atl ?
I currently have Ware in my Flex with the upside of Mahomes. But, i could see Edwards having a decent game vs Atlantas def.
League is .5 PPR