I'm reading the Target novelisations alongside a rewatch of the classic series; and my reviews will be focused on the novelisations themselves more than the story.

The TV story is a great first episode introducing the characters/story arc leading into a distinctly average story that also is as much focused on introducing the Doctor, Ian, Barbara and Susan as in telling a compelling story by itself. Terrence Dicks' novelisation (which was written incredibly quickly; as this good was intended to cash in on the 20th anniversary of the show and an accompanying TV airing of the serial) is a good retelling of the story that was on TV and conveys the various rivalries and dramas present in the TV version more clearly; but it also doesn't expand on the version that aired on TV.

The actual writing itself is good (as you would expect from Dicks) and its clear why in a world before home video these books were very popular with readers; but in the world of today where the TV serial is easily available on DVD this is a novelisation that could be skipped.