Penn and Teller Get Killed isn't what you'd call a triumph of skilled film-making. The primary function of the movie is to allow Penn and Teller to perform their routines and display their trademark style -- a style that has as much to do with their attitudes as it does their 'magic.' If you like them, you'll like the movie; if not, you probably won't.
That said, the plot is interesting enough, and the film is not JUST a vehicle. The film itself really does reflect their twisted sensibility, and that may be its strongest point -- it's not just "Penn and Teller do some magic with a plot pasted on." It's really what you'd expect if someone allowed these two to make a movie. (The ending, in particular, is one of the strangest I've ever seen.) The film is perfectly Penn and Teller: it gets inside your head, twists things around, breaks some stuff, and leaves with a smile as you try and figure out what to do with the mess.
That said, the plot is interesting enough, and the film is not JUST a vehicle. The film itself really does reflect their twisted sensibility, and that may be its strongest point -- it's not just "Penn and Teller do some magic with a plot pasted on." It's really what you'd expect if someone allowed these two to make a movie. (The ending, in particular, is one of the strangest I've ever seen.) The film is perfectly Penn and Teller: it gets inside your head, twists things around, breaks some stuff, and leaves with a smile as you try and figure out what to do with the mess.