The documentary website says:
Heavy Load are Lewes' answer to the Ramones, a punk band subject to the usual inflammatory mix of ego, fantasy, and desire. They're also, uniquely, made up of musicians with and without learning disabilities. The bands' survival is a precarious negotiation between two different worlds: on the one hand the institutional timetable of day centres, work placements and social workers; on the other the chaotic slacker life of rehearsal rooms, studios and gigs. Home life and band-life; from invisibility to stardom of a sort and back again. But this is not a film about a young band on the road to making it. Specializing in thrash covers of late 70's punk - or punk versions of recent pop, Heavy Load are unlikely to have a top ten hit. Shot over two years as the band record their first album, the film is a comedy of conflicting ambitions, as the band move out of the ghetto of disability club nights to test whether their dreams can survive in the mainstream.
You can get a copy of the DVD which includes extras such as their trip to NYC from http://www.heavyload.org/.
To find out more about the film, see http://www.heavyloadthemovie.com/.