What worked for Planet Terror: it is awesome as a "disease" or "outbreak" movie. Even though the film is generally darkly lit, the killing of the infected proves to be action-packed and very bloody (did Tarantino ghost direct certain parts)? Wray is a really cool character with a clear expertise on guns and a great shooter. Cherry is good as well, but a little more bland than Wray. While the coolest aspect of the film has to be when Cherry gains a gun for a leg it defies the logic of her knowing how to operate it without pulling a trigger of any sorts. Also, it does not seem to run out of ammo. But this logic is somewhat irrelevant since it is clear Planet Terror was made for fun.
What worked for Death Proof: Tarantino is at it again with conversations that connect dots between various situations. For example, in the first half of the film a girl is told to do a lap-dance for the first man who says something specific to her, and her friends urge her not to be "chickens***." When Kurt Russell tries this on this same girl later in the film, he makes an analogy to the common phrase "in my book" and threatens to put this girl under "chickens***" in his "book." Unlike most Tarantino movies, however, it lacks substance, and at its most basic, Death Proof is about Kurt Russell tracking two sets of girls - one in the first half and another in the second half. Even with Tarantino-esque dialogue, this segment falls short of great, but Kurt Russell's performance in this movie is convincing and impressive.
It is a fun experience to watch this double feature, but do not expect to watch two masterpieces by any means.