I loved Sunny, her resourcefulness and cheerful disposition. I got thoroughly annoyed though at how quickly each of these virginal heroines "realizes" she's in love with the guy before they have sex. With Mackenzie's Mountain, Mary and Wolf almost - almost - had enough time and contact beforehand to make it believable. It annoyed me in Mackenzie's Mission though. Then in Mackenzie's Pleasure, there was no question of love before sex and I appreciated that - though not as much when they retroactively "realized" it. But at least their circumstances were extreme enough to almost - almost - make it plausible.
The circumstances in this story were extreme too, and Sunny notes that as part of the reason or explanation for the suddenness of her falling in love. Perhaps it's plausible here too, but by the time I got to this book I was just sick of that theme. I tried to remind myself of the time period and context, but it was still annoying.
Other than that, I enjoyed it.