The series anticipates a lot of the ideas found in Shine Entertainment's more recent series (2008-2012) with Merlin training as a mage and working to prepare for Arthur and himself to discover their destinies. It is also very similar to Mary Stewart's novel The Crystal Cave published in 1970 (and adapted to film in 1991), but embraces the magical elements of the character rather than rationalizing them.
The pilot from Shadows and three of the six episodes from the series are available on YouTube (see below).
A trailer for the Region-2 DVD set is also online and includes footage from yet another episode.