The Walking Dead: Survival Instinct is a slipshod, uninspired mess. I have to feel for the developers at Terminal Reality—whatever rushed production schedule or other behind-the-scenes shenanigans must have gone down, no professional game-maker could be happy with this final product.
There are so many superior alternatives: If you've got a hankering to kill some zombies in a southern setting, play Left 4 Dead 2. If you love The Walking Dead and want to spend more time in that world, play Telltale's wonderful adventure game from last year. And if you want to play a tense, terrifying first-person zombie game that relies on smarts and sneaking as much as on firepower (and you own a Wii U), play ZombiU.
I can think of no compelling reason why anyone should play this game. Ugly, flat, boring, aggravating and often broken, The Walking Dead: Survival Instinct is the purest form of video game garbage. It's utterly unworthy of your time and money.