The book gets off to a rocky start. The language is awkward, the description (and the situations themselves) cursory. There are frequent and unposted changes of point of view. Much of the plotting is perfunctory, and in fact, the book often reads more like a description of someone's role playing game than as a true story - there are lots of puzzles to solve, and very little actual risk.
That said, the story is engaging and interesting - enough that I wish the supporting writing had been stronger. I'd be interested to find out what happens, which is at least one sign of a good story.
I'm not sure, though, that I'd be willing to read another. For one thing, the characterization has pretty strong overtones of machismo, homophobia, and outright sexism. For example, the male protagonist suddenly realizes he's holding a man's hand, and hastily lets go. His wife, in the unfortunate Heinlein/Jordan tradition, is smarter and more capable than he is, but needs protection from the harsh realities of the world. In the 1950s and 60s, this was the norm. It's not now, and it's a bit hard to take. In addition, there are fairly frequent consistency errors, errors of language (compliment/complement), and copy-editing that's not the best.
Immediately after I finished reading, I was interested to see what was next. On brief reflection, I'm not as enthused, for the reasons above.
Overall, a decent, fast-moving, and fun exploration of fantasy wish-fulfillment, but substantially held back by poor editing and outdated attitudes.