How does the Camo suit work?

My game occasionally messed up saves and froze a lot between 30 and 35 hours in.

According to the Prima Official Guide:

"The camo suit is the single most expensive item in the game, but it's well worth every diamond--the suit is automatically applied to your character upon purchase. While you're crouched in tall grass, the suit makes you almost invisible to the hostile AI, even enemies standing only a few feet away. However, the effect is lost if you are detected by shooting, moving, or standing up. So if enemies are nearby, stay low and stay still until they're looking away from your position, then either take them out or move to a new position. The camo suit is most effective when you use silent weapons, like the Dart Rifle. With no audible report to zero in on, the enemies won't know where to begin searching for you. And even if they do, they'll have a very hard time detecting you."

This is a direct quote from the Official Guide. Hope it helps. :)