The network code may not be up to snuff, but No Mercy sets a high bar when it comes to downloadable games. No Mercy is built with the Unreal 3 Engine and looks like a retail game. Levels are big (probably too big, but more on that later) and the level of detail is impressive. There's a dose of requisite grays and browns, though Zen Studios has done its best to brighten things up with lighting and atmospheric effects like fog.
Audio is forgettable except for gratuitous use of "F---" every couple of seconds. It's to the point if you were to bleep out every instance of the word you would mistake the game for the Emergency Broadcast System. Okay, so I'm exaggerating... but you get my point.