I liked the book more than the series. But it's an old book and it shows. Also, the male gaze is overwhelmingly present, which nowadays is... a problem. It is usually subtle (and sometimes not so subtle) but once you see it, you can't unsee it.
Still, I think he did his best to write a strong woman. He did what he could, at that time.

The story moves along quite well. There is a lot of repetition in story patterns, and the story structure is rigidly formulaistic, but that's ok. This isn't about plot. This is about the main character and her development.
I like that he doesn't take some of the easy outs. He refuses to go with some of the tropes that treatened to jump in.
I was very annoyed with the inclusion of the one single 'handsome' boy as a possible love interest, but he ultimately didn't do anything with that.
And I loved the ending. Beth going alone to Russia, on her own. That phonecall could have made that go wrong ("strong woman still needs a man to rescue her"), but no, that she still did on her own..

I haven't read non-fantasty/scifi/specualtive fiction in ages, but it was a delicious in-between snack.

Quick warning though:
I read/listened to the Audible version. I absolutely hate the narration. It is bad. Look, I understand there were some bad narrators in the past, but come on, this is a freshly narrated book. The standard must be higher than this. This sounded like the ran the book through Amazon Polly. It was robotic, with sometimes weird/wrong emphasis or pronunciation.
There are plenty of excellent narrators out there. Just don't go for the budget robotic one ok?