As for the mirrored Diamond map, there's less information available – it's played less often, and it doesn't have an equivalent in WT, so the tournament run is shorter. From my personal observations, I'd say it's slightly more entertaining than h3dm1, as the contact happens earlier. But how the players themselves perceive it – let them speak. I got the impression that guessing the direction plays a slightly bigger role there than on h3dm1.
As for the mirrored Skirmish map, I really don't know; I've only seen one game, and according to reviews, the tavern plays too big a role.