I've played Dungeoneer Tomb of Lich king through Vassal and liked it, so I've decided to buy one pack. Haunted woods is the set that appeals to me most thematically, but there's one problem I'm afraid of. Is 10 map cards enough for a play? At the beginning you already put on the table half of it (entrance + 4 passages). That means that whole map is created after 5 turns. Doesn't the game end sooner than in 40 minutes as it's written in description?
One more question. There are 3 new characters. Is it playable with three players then?
I only play Haunted Woods as a quick 2 player adventure. The map does feel small after playing Lich Lord or the larger sets, but it is workable with only 2 players. Another possibility, that you don't mention, is that you can combine Haunted Woods (as the "outside") and Lich Lord ("the dungeon") together. For the price, I think the Haunted Woods is a good buy, but be prepared that it is much smaller, fewer items than the double-pack sets.
The single deck sets contain half of everything that the double deck sets have. As far as the map, I prefer the method where the map is laid out from the beginning, so I think the map being completed sooner is better. As for the number of players, it does not have enough quests for three players, just like the double deck sets have six characters but only enough quests for four players.