Clearly PC wins in terms of graphics, then PS3, then 360. Anyone who says otherwise is a fanboy in denial, or just needs glasses. Although, as others have pointed out, most people don't play Portal 2 for graphics.

I really tried not to use this as much as I could (it is a puzzle game after all), but it's nice to have something to fall back on when you're completely stumped and wondering around like WTF man. The last three chapters are the only ones I was tempted to use this guide.