This is the kind of book I love and MagLagan did a fine job with it. There's lots of danger, near death, and injury. The love is too fast but the characters acknowledge that this could be because of the one we situation they were in. I liked both characters and didn't think either was TSTL (at least after Nick realized there was really a threat). There was only one sex scene and it was hot.
Happy ending? Well all the LHNB stories do. It's a requirement!
3.75 as the whole thing is formulaic but rounded up because I really enjoyed it.