WHO TO PICK UP for my flex! Need this #footclantitle

Who do I pick up!? I am in a league where waivers cost $5 per transaction so there are a good crop of guys out there to pick up this week…I am currently rolling with Gallup in my flex so the question is basically should I play Gallup over these 4 guys and if not, which of these would be the guy to pick up and play?

FULL POINT PPR
Mostert
Deandre Washington
Perriman
Boone