I was too slow to grab this on first release, but managed to "see" somebody else's "OPEN BOX" and was very, very impressed. I have to add that I am not a Samurai buff myself but nevertheless could feel myself tingle at the quality of the game (see below):
Hope to be able to pick up a version on second printing! The figures looked stunning (though apparently fiddly).
It has all the hallmarks of a "one box" game and extensions only if you want to!