Played a 5-person basic game (original game, no changes except for switching the Greyjoys on the Kings Court track) last night. Starks and Lannisters were new to the game. Everyone else had played at least a couple games.
Greyjoys won in turn 6, had a chance to win in turn 4. Tyrells' fleet had been trapped between the Baratheons and the Greyjoys, and ended up retreating east; the Lannisters attacked the iron fleet inadvisedly and lost both their ships; and the Starks were never able to put together a fleet that could challenge for the West. Starks, unchallenged up north, were slow to move south and to collect supplies/cities, which allowed the Greyjoys to take advantage of musters to build fleets (first) and (then) armies without fear of losing the fortresses in the center of Westeros. Baratheons' lack of supplies hurt them a lot, and diplomatically, they hurt themselves by orally threatening both the Tyrells and the Lannisters, which meant the latter houses' attention was directed east instead of towards the growing Kraken menace.
A good game.