This is one I actually like quite a bit, even though it not generally well-loved. Don't know why, actually. Maybe it's because of all of our TARDIS team has great moments throughout the story - particularly Zoe-gond, err...Zoe.
The Krotons themselves are kinda interesting to look at, if not very convincing as being threatening.
Philip Madoc being in the cast is good for a few points, too. He's always excellent.
SeaDevil