First, the bad: While I can understand that Marguerite is a woman in love, some of her stupidity at the beginning bordered on unbelievable (I don't mean this as an offense to Margot, who is one of my favorite characters, but if you read this book, you'll understand what I mean when I say she makes a bad decision). As usual, Percy becomes a secondary character in his own books, and that bothers me. Lastly, the choice Chauvelin gives Marguerite and Percy gets to be a little too much.
The good:When Percy is around, he really shines. He has some really great moments in this book (which I won't spoil). The reader gets an idea of some of the emotions that are going on behind the facade. Also, "Elusive" has much more of a climax than some of the other Pimpernel books, which is a nice relief. Lastly, Desiree Candeille is an interesting character.
In all, I would recommend Eldorado between Elusive Pimpernel, but it's still a good read anyway.