I say Hashirama win because of edo regeneration and because he beat Madara the the first time and can control the tentailsand has a giant scroll filled with jutsu and multi wood clone jutsu to create an army of edo wood sage mode clones in the hundreds or thousands
I think Madara because he eventually grew stronger than Hashirama even if Hashirama was stronger than him for a long time.
But it's hard to say and I don't really have any better arguments than you.