Deden and John provided a great tour with lots of information about the region and the mining operation. Deden was very mindful about us reaching the crater safely and helped us during some of the trickier parts. It was very much worth it and we would love to take another tour with them some day.
Positive experience, great guide. It was a long walk up and down but definitely worth it.
Just make sure you do not go too slow on the way up as you need to get to see the blue flames as it gets too busy and lots of people missed out.