Quantum Theory runs with the same "Destroyed Beauty" theme that Epic Games has been implementing in its now classic third-person shooter franchise. Syd is an ugly, scarred hunk of meat, but he's supposed to look that way. I can't get any further into the topic without risking spoilers. (Not that you'd care.) He could pass for a former Delta Squad member, but only if he was dishonorably discharged after taking a bath in a high octane imulsion pool. Filena doesn't do much to change the public's perception of Tecmo's character design trends. She's a fair-skinned buxom warrior, 'nuff said. The tower that drives Quantum Theory's story along has an interesting look to it; the best way to describe it is "opulent and organic." Kind of like Nexus in Gears of War 2...
The best parts of Quantum Theory's sound design are forgettable, with maybe one exception. As Syd makes his way to the top of the tower, a heavily-distorted voice can be heard over an intercom system. This makes it abundantly clear that Syd is being observed from a purely scientific standpoint, and the almost monotonous delivery actually works to the advantage of the game's admittedly weak atmosphere. The rest of it is either mediocre or worse. The music doesn't really score any points for or against the game, but the voice acting is bad. Of course, the poor guy voicing Syd doesn't have anything to work with -- apart from choice one-liners such as "Die," "Heh. Splat," or "Mmm... Ammo."