Consider the title a disclaimer. I'm the guy that started the yahoo group that is referenced on his web site. Ok? But I wanted to reply to a couple of the issues raised in other reviews.
How do you define military sci-fi if taking one of the greatest war machines of the historical era and transplanting it into a science fiction universe does not qualify? This is a story about a group of Roman soldiers, and the tribune who ends up commanding them as they travel through the galaxy, serving unworthy masters, and what they do about it. Statements suggesting that it is a set of loosely connected stories are made by people who haven't read the book.
Drake considers this one of his more artistically successful stories, and suggests that it sold well too. Jim Baen wanted a sequel so much that he got Drake to agree to one of those shared universe anthologies, and the sequel is more fun that it is legal to have in most states. Luckily, I live in Nevada, where the only thing that is illegal is being a non-smoker.
If you like military science fiction, by a man who has been on the sharp end and mostly came back to tell us about it, get to know Drake.
As for space opera? Try his Leary/Mundy books.