I love this game but i'd love it more if there was more of it.
The gameplay is quite unique. Even though most of it is mashing the square button, and sometimes triangle, there is a really cool feature called "Kamui" which doesn't make you any more powerful but makes an enemy attack you and if you time it right you can execute an effective counterattack that usually kills regular enemies in one blow. You can even use this special ability without Kamui if you have excellent timing. Its extremely satisfying just watching your enemy just splitting in half when you're done with them. You can even buy different weapons and armour to slice up your opponents better and prevent you from being sliced up.
Even though this game is thoroughly amazing it doesn't exactly have the longest time of gameplay. My first time going through the story was counted at about 13 hours because it took like three hours to kill the last bosses. I did it again because I switched from ps2 to ps3 and my data was lost (I don't plan on buying the memory card adaptor). When I did it again it took like 9 hours because i never died. Well, I died twice but I had this item on me that made me get a second chance both times so I never got that elaborate "the end" sequence.
So overall this is a great game that was maybe a little too short but you should buy it anyway instead of renting so Game Republic can make a third sequel that is longer.