This book was so good I pretty much devoured it over the weekend. I really like the psychosocial horror elements, and very much reminded me of The Descent. 

I will say I didn't really like the implications of the ending (

the trauma bonding to love aspect

), although I can see clearly how we got there.  I also wish we got a quick overview of terms for those of us who don't cave (for the first third of the book I thought cams meant cameras, since I didn't have the knowledge to know that cams are equipment), but other then that I think she nailed the balance between being informative and knowledgeable with the topic, but not over explaining things (Dan Simmons I'm looking at you).

Overall an amazing read with a bit of a weak ending.