At best I would round Heart of Fire to a 3 ½ star and it has nothing to do with the writer either because I've read her work before but I wasn't taken by this one and it kinda fell short for me personally.
Let's talk about the characters, I wasn't impressed by either Gerilynn or her mates and maybe that's because for me the story was too fast-paced and I think it has the potential of being more had it slowed down a bit because I didn't get the chance to learn more about Gerilynn and her mates beside them being the very cliche mates destined to be together for life. Again, this is no fault of the author but that of a reader who tends to be a tad more critical of stories like this one.
The intimacy was lacking too, but that was due to my own expectations of having three sexy dragons at your disposal. I thought there would be a burst of excitement and saucy teasing but it went by with a breeze. The unexpected betrayal as well I thought could've been elaborated more for me to understand the power struggle and the dragon's way of life.
Gerilynn’s kidnapping though abrupt was slightly entertaining and I enjoyed that a bit as well. I could go on but like I said the story was just too fast-paced for me to thoroughly appreciate it and even so I would still recommend it because it has quality.