We tested a KWA at 3 feet away at full auto, reflected all the shots and left no damage. There's a little vision distortion while wearing the mask, but it's not a major problem and it takes some getting used to. You can wear eye glasses underneath too, which is good. The fan system is virtually silent, but you don't need to leave it on all the time. You can toggle the on/off switch to blast some air when needed.
It's been REALLY hot and humid here in Georgia this week, so having a fan in your mask is a must-have. considering the bulky size of the mask, it's very lightweight and comfortable for a 'gas mask'.