Watched it today, not entirely like Mean Guns. The whole teams of killers trying to kill each other is all it has in common with Mean Guns. The plot is entirely different. I'd give it a 6.5/10. Worth a watch, but it's not gonna set the world on fire.
Also, Galifianakis doesn't have a huge role, Corrdry pretty much plays the same character he did in Hot Tub Time Machine, and Odette Yustman is too hot for her own good.
But it's worth watching. A little convoluted trying to determine whether this is a comedy or an action movie, they never really blended them together very well. But the comedy was funny and the action was serviceable. Solid movie, definitely check it out.