This is one of those shows I loved as a child in the 1980's, that I had no idea was actually anime. It's always a gamble revisiting shows beloved as a child as many won't hold any appeal to you as an adult, but I found a lot to enjoy in this series. The first of the four story arcs is the same as that in the 1939 Oz film, but the later three are from different Oz books, with various changes. Things really take off in arcs three and four with the introduction of the Gnome King.
The Canadian English dub has variable performances, but Morgan Hallet as Dorothy has the sweetest, loveliest voice. And the music in the English version has an undeniable nostalgic attraction, as upon hearing it I'm immediately taken back to childhood. The original Japanese version with English subtitles is sadly not available, but there are a couple of full episodes on YouTube (on Discotek's channel) and as usual for 80's anime dubs, plenty of dialogue was added to the English version.