This film is intrinsic to many people of my age who remember the television series from their childhood. Sure the acting is not great, the story is nothing to do with the King Arthur legends, sure the costumes are vaguely 70's hippie inspired. But its great fun. In my opinion the Arthur legends are at best interesting at worst lies. No one will ever prove King Arthur existed. However if you do think he existed than in reality he was probably like this film depicts. A Celt warlord in ancient times. The cast list includes many young actors who went on to be famous so perhaps they where learning their craft.
My advise get this film its great fun. It's not meant to be serious. Plus its a film spin off of a 70's television series in the UK.