When things are simple, it's hard to screw up. This is the principle behind Fast Five.
It's not a terribly complex story, but it works in the movie's favor. It's about fast cars and explosions, character depth is unnecessary by design, so try to ignore the forced relationships, shallow characterization, and empty dialogue. You'll enjoy the movie a lot more that way.
I enjoyed the movie, even though it still suffers from frenetic Hollywood shaky cam syndrome. If it weren't for the nonsensical "gritty" screen shaking, one could actually appreciate the complexity and composition of the stunts. Alas, the world of action movies is forever tainted by the Bourne Supremacy.
Curse you Paul Greengrass.