I picked a copy up on Tuesday and am running it tonight with my gaming group, many of which have not looked at much of the 4th edition rules.
for those interested, as well, WotC also created a sixth character for KotS - a Tiefling Warlord. Our party has six players, so that worked out well for us, but it also gives people that want to run the campaign another character to work with - as well as trying out the new player race and class.
I also love that adding the extra character takes NOTHING as far as scaling. “what, another first level PC? ok, add 100 XP to the encounter and we’re on our way...”
edit: as far as the quality, my copy has been good so far - no issues and i’ve read through it a number of times as well as had many people looking over the character sheets.