Actually, it's almost a touching coming-of-age drama; except the ones growing up are a pair of adult metal heads who spend their lives shotgunning beer.
The whole film is very raw, edgy stuff; blurring the boundaries between “mockumentary” and documentary. It's easy to compare it to This is Spinal Tap, but this takes the fictional documentary so much closer to reality. The lead actors give a performance that's so convincing it's hard to believe it isn't more than just method acting. From the titles, the sequences, and reading around, it seems that part of the film features some people who didn't know that what was being filmed was fictional.
The scene with Dean ranting against fate and God during a thunderstorm may have been clichéd, but was very powerful.
I had trouble not singing along to the soundtrack at times; putting AC/DC Jailbreak and Iron Maiden Run to the Hills on the same film soundtrack is just unfair.
A film like this, dealing with testicular cancer in a very real way, could be socially valuable. It should probably be shown in schools to teenage boys before they get the embarrassing little leaflets about testicular cancer.