I'm taking a halfling rogue into it in a campaign starting in the Shattered Gates of Slaughtergarde published adventure; it's going to run into the Red Hand of Doom when we're done. You'll need some fighter levels to take best advantage of it's features, unless you can talk your DM into letting you use the concealment instead of armored ease variant they talk about later in the class description. (I did.) Sudden Strike is less versatile than Sneak Attack, but the increased durability and the ability to remain mobile while hiding (not to mention the bonus to your party's Initiative checks which, by the way, stack with that given by a marshal because it's competence instead of morale) make it worth the trade-off for a rogue that's going to spend a lot of time on the battlefield in my opinion.