Haven't seen this for donkeys years. Very solid story, and the cliffhanger to Part 1 is memorable (part 2.....not so much!) I'd say Peter C makes the 'Doctor talking to himself' bits more convincing than Tom, who's a bit 'broad' at the start, but things settle down nicely once Leela meets up with him. Decent script and generally good performances, and the filmed jungle set still holds up very nicely. (Planet of Evil's is even better. Quite superb, in fact.)
Nice stuff so looking forward to the second half. Interesting concept to have the Doctor having such a dramatic effect on a planet by accident, and the imagery of him climbing over 'his' impressive choppers was cool...I seem to recall the second half is a bit more 'running around corridors a lot' and not *quite' as strong, but will see later...