The first one was interesting but a bit rushed - he had, I think, edited a book about various great journeys of exploration in history, and obviously had a lot to say about them, but not much time to say it all in. We got little fascinating comments about various explorers, but you needed to know a bit about them already to get the best of it - I did for some, and didn't for others.
Should be a good book, though (I can't track it down on amazon, so it might not have happened yet).
The second man had taken what seemed like an interesting subject - the journey from the Ramayana, a very old Indian text - and managed to mostly talk about himself for 20 minutes. I know there were interesting things in there, about old civisilisations, and a land bridge from India to Sri Lanka, and just the sheer range of interesting things in this world, but I didn't feel he did a very good job of putting it across.
And now I have discovered that there is a whole series of books about Great Journeys, and I am not supposed to be finding ways of spending more money!