I'd favour Shawn Porter quite comfortably in this fight.

maidanas power is abit over rated. He landed his best shots flush on amir Khan for 12 rounds and couldn't drop him once. His best win was broner who porter also beat but had the disadvantage of a catchweight.
the stoppage win over Ortiz was also repeated by lazcano, berto, collazo and Floyd and none of those guys were renowned big hitters.
porter had the physical strength to take maidanas heart like Devon Alexander did IMO.