The idea is superb. I read the Landmark Thucydides, Herodotus, and Xenophon. For Thucydides, the maps are a wonderful addition. For Herodotus, they are less useful since the locations don't matter as much for the narrative arc. Or at least, having a map on the facing page is not as useful. Xenophon, I think the problem is that Xenophon's history is possibly the worst sequel of all time, and deserves to be as unread as it commonly is.<p>The translations are not the best available. Unfortunately. But Herodotus and Thucydides both repay rereading. If you haven't tried these, do! If you have, try a different translation the next go round.
I have Thucydides and Herodotus, both are amazing. I don't know how I would read Thucydides any other way. There are so many place names and directions, you really need the maps these editions provide.