It's unfortunate that this novel isn't more widely known about, as it is the prequel – the OFFICIAL prequel – to the Mass Effect game series. And it's good.
It's written by one of the actual game story writers, Drew Karpyshyn, so there's no continuity issues and it all gels together with the game universe nicely. Some of the characters featured exist in the games, and their stories have been interwoven rather cleverly with some new pro/an-tagonists.
And yes, he stands up perfectly well on his own as a “proper” author, the writing style being easy to digest, and suitable to both quick pick-up/put-down and extended marathon bookworm sessions.
Perhaps my only hesitation overall, he does seem to relish, slightly too much, opportunities to describe gunfire-mangled limbs and the process of torture sessions – sometimes these extend to many paragraphs, and you start to get the impression that he enjoys this imagery just a tad more than would be considered healthy. This isn't stuff you encounter in the games for obvious reasons, so maybe this is an insight into what the series may have been like without censorship boards to appease…
But there you go. Like the games? Give this a whirl.