First up is Sengoku Basara: Samurai Heroes by Capcom as the head guy that was behind Devil May Cry 4 is the head honcho for this project. If you played any Dynasty Warriors games, this one is pretty much that in a nutshell as you mash the attack buttons to pummel hundreds of enemies that just stand there mostly to get killed. Other than mashing, you may have to dodge some attacks here and there by tougher boss-like foes, but it is pretty much what I described earlier if you're into those type of games. There are two characters to play as in this demo and one scenario that is long enough (like 20 to 30 minutes) defeating waves of enemies gaining new allies in the process for world peace. Some of the attack animations look like Devil May Cry 4's which is why you may get a familiar vibe if you played that game to death also by Capcom. Some of the allies you gain feel useless, so you feel like you're doing all the work, which is not that bad. There is a Basara gauge that gets filled up for one powerful attack string that uses the meter when full, which is useful if you're in trouble. Other than some camera control issues that struggle to keep along in the action, Sengoku Basara: Samurai Heroes is a solid Dynasty-Warriors-like game if you crave those type of repetitive gameplay.
Quantum Theory, on the other hand, is a whole different story. Oh boy, what happened to this game since it was first announced by Tecmo two TGSes ago that has some potential to be interesting being a "Japanese Gears of War?" It definitely feels and plays like Japanese Gears but in worst ways in all areas. Honestly, it is one of the worst games I played in recent years as everything feels bad you feel like why did I wasted all this time to download this and play through the whole demo. The cover-based shooting does not feel as satisfying and fluid as you expected being a Gears clone. In other words, you feel like you have to press more buttons to pop in and out of cover compared to how automatic the Gears games handle cover controls. The weapons feel generic with nothing special such as a single shot rifle, a machine gun, shotgun, etc. Even the melee system feels complicated and disappointing if people expected Quantum Theory to have some Ninja Gaiden flavor. The only redeeming gameplay element is the partner commands in which you can throw her from a distance to take out foes from afar, but even that has its flaws as well.
Besides the overall gameplay being flat out bad, the graphics and sound are more worse. Graphically, it looks like a darker and grittier Gears and yet it is more ugly. Add along poor level design on how the encounters are handled and bad enemy A.I. that just stands there at times to shoot, you have a bad ripoff that even shames the original. To top things off, the voice acting is abysmal with generic one-liners at any moment as the main guy just sounds dumb saying these pointless lines like "mmmm ammo." and the partner chick telling you "nice shot." The main character looks and sounds like the most cliche space-marine dude you're ever meet in any game because seriously its that horrible.
Playing something like Quantum Theory makes you wonder why games like this get green-lit to be released in stores. It is an abomination unlike anything I played in recent times, which is saying something for myself too. Avoid this game at all costs, or better yet play the demo for yourself and see how horrible it is.