So, the good news is it is far from being the worst thing I've ever played. Actually technically at least the PS3 version looks great and runs fine. It hitches up a little bit when auto-saving but other than that I never really noticed the frame rate dipping to horrible levels.
It also looks pretty damn nice. They were going for a comic book style and by god that thing looks like a comic book. It feels like they took Comix Zone and Ninja Gaiden and smashed them together with a dash of Duke Nukem for seasoning. The entire thing feels like it should have been an arcade game.
The game starts off and you get little to no reason why Yaiba wants to kill Ryu other than he is an asshole and then Ryu promptly kills Yaiba which sets up the conceit of the game. You're then just instantly dropped into a city full of zombies to hack n' slash through with no real justification for why the zombie outbreak is happening or why this busty red head Ms. Monday keeps popping on your screen talking to Yaiba like she knows him or better yet why Yaiba is even agreeing to go along with what she is telling him to do.
That being said the game has its moments and its ideas that seem almost cool. And that is really what this game is a game of almosts. The one interesting mechanic it has is that various enemies can have their body parts ripped off to use as a weapon. An early game clown zombie can have his arms ripped off to form wait for it.... Nun-chuckles. Its almost a cool idea until it basically devolves into just stunning enemies hitting a button winning a small QTE event and getting rewarded with your weapon. Had it been a more tactical thing where various attacks might lop off specific body parts that you could then harness it could have been a way more interesting mechanic. One of the things that really feels lacking is the level design in fact Id say the level design is one of the worst features. Also, levels are pretty linear. You'll go down a path kill dudes then go down the path further to kill stronger dudes.
So in short should you buy it or at the least play it? I would say its worth a buy at any price point from 30$ under it has some charm to it as brief of flashes as they are. It won't be the worst game you'll ever play its just sort of well... a really mediocre one. Feel free to shoot questions if you have em'.