Rating: 
This is an intentionally cliché fairytale for a younger audience. The story follows a unicorn and a struggling wizard on a journey that involves a demon bull, an evil ruler, and a prince. It has darkness to it but is still quite simplistic. The story is quite boring overall, although it does improve a little in the second half.
There is much love for this story online, perhaps because people first read it when they were young. As a latecomer, I unfortunately found it to be bland, conventional fantasy.
Despite being read by the author himself, the reading was not particularly enjoyable. Beagle sounded like he had a cold, and simply was not as good as the voice actors we’ve become spoiled by.
There was fantastic music (classical guitar) between chapters which was a pleasantly surprising feature, and the best part of the listen. The short bursts of music were the highlights of this story, however were unfortunately not enough to redeem it.
Perhaps it would be better to check this out in its other formats (e.g. comic, film), however if The Last Unicorn read by Peter S. Beagle forms part of your future, here is a link to it at Audible.com.