Bit of necromancy here, but I finally got to see this movie. Japanese Netflix, no English subtitles. Didn't help the experience, but overall I'd say it wasn't great. Online reviews have it about right- lots of talking (not that I have a problem with that), too many ninjas, and the battle is...ok, at best. Some odd aspects- Crossbows, axes and hammers feature in the fighting. But overall it's just a bit underwhelming. Worth a casual look, but not really worth hunting down.
Shogunate's review is about right.