What to Expect
Expect a story happening in parallel to the previous novels. This could be a different starting point (at least for those not minding to see the 'end' in a way). The protagonist is a low-level diplomat in a foreign country, who only hears about the events 'back home' that happen in the previous two books.
Expect the usual for this series and the KJ Parker style in general - a low fantasy based on antiquity (no magic, just an alternate world), where a normal person ends up changing the fate of empires with a combination of shrewdness and luck. Sometimes without really meaning to - intended and unintended consequences are a theme running throughout the novel.
What I liked
I love how Parker uses real nations and people from antiquity as the basis for the fantasy world. You can almost-but-not-quite place everything and everyone. It leads to unique world settings, different than your run of the mill ones while at the same time hauntingly familiar. Of course, it's not just the cultures but the whole human nature that Parker is so adept at describing, which makes for a story that is both entertaining and insightful.
What to be aware of
Parker's protagonists aren't always the most active ones, often showing a certain reluctance to get into the action (which is probably a lot more sensible than your gung-ho adventurer). There also a few passages, mostly towards the end, that are a bit dragging. Those are usually in the service of the 'point' of the novel, which leads to endings that can be both frustratingly anti-climatic and the only possible way things could have ended. Again, thought provoking more than mere entertainment.
Felix obviously loved the name of the protagonist (another Felix), and felt immediate kinship. He recognises the drives of someone who's good at something, but more than that is simply intelligent and likes to read a lot. Though he wouldn't necessarily go quite as far, he also applauds Felix for what must be the biggest con in history - very much in like with the previous protagonists.
This is fantasy at it's best. Though not sword-and-sorcery adventures, it uses a unique setting to explore human nature and our own ancient history (while still wrapped up in an engaging story told by a relatable character). You can jump in here as events happen (mostly) on the side of of the previous books, though I would recommend reading in order for a better experience (starting with Sixteen Ways to Defend a Walled City and continuing in How to Rule an Empire and Get Away With It - gotta love those titles!).
Enjoying the reviews, but wondering who the heck is that Felix fellow? Glad you asked! He's the protagonist of the Togas, Daggers, and Magic series, an historical-fantasy blend of a paranormal detective on the background of ancient Rome.