Interesting fight. I think I'd favour Harding - not a devastating hitter, but probably more variety in his punches, great at working the high-low, and with the stamina and durability to boot. Even when the other guy was carrying the action right to him (like Andries did, especially in their third fight) he had the ability to make room for the shots and get off more consistently than them. I think Harding wins a decision in a dogged, gruelling fight.
I'd pick Harding too, he seems like a higher class of fighter and would out-hustle Lalonde. Although, outside of their best known fights, I've barely seen any of these guys.