Great way to escape the crowd of tourist and do so...

Great way to escape the crowd of tourist and do something special. Be aware that it is cold and wet (is a cave and the glow worms like running water) and that the gear comprised of wetsuits is, as the name says, wet and therefore cold. The changing rooms and hot shower will help restore the body temperature as well as the soup and bagels in the end of the experience.
I did the 5h black abyss and Matt and Cian (Ciarne) where funny, knowledgable and did not spare efforts to inform, entertain, try to take good photos and keep everyone safe.
They did not forbade anybody to take their cameras, they just did not advise it since one could lose said camera.
For what I understood, the company is obligated to pay for the right to take photos, since they don't own the caves and they are just "renting" the right to use them. What our group did was, share the costs and forward the link to everyone's email.
About the experience itself, there is not a lot of thrilling radical emotion going on. But it does not take away the beautiful feeling of being in the dark in a cave, surrounded by water, silent, glowing worms and away from the crowds.
Would recommend always but adjust expectations regarding the thrill of the rafting/caving.
Thank you guys!
Joana