Which is not to knock Brute Force. For what it is, which is a basic shooter, it's a decent one. But because Microsoft did everything they could prior to releasing this title to compare it to Halo, it's worth stating clearly and loudly: not even close.
Whereas Halo is an elegant, incredibly immersive first person shooter with a deep and well paced engaging storyline, Brute Force is simply a third person run and gun shooter. Which, again, isn't bad if that's what you're looking for.
But as with the Halo comparison, that's not how Microsoft marketed this title either. Brute Force was supposed to be a genre defining title, a team tactics game where you got the lay of the land with your recon unit, followed up with your heavy gunner and backed him up with your sniper.
But the game doesn't have a whiff of such strategy. You can basically go through most of the levels controlling one of the two male characters and blast everything in sight.
Personally, that type of gameplay gets boring pretty fast. Contra was great in its day, but gamers seem to want and expect more out of their gaming experiences nowadays - and unfortunately Brute Force doesn't really deliver.
Were it not for the System Link option and various multiplayer and co-op options, the game would rank a 7 at best.