I've had this for over 3 years, and I've noticed a few problems. First, it fogs up now and again despite the ventilation holes. Second, there's a bit of visual distortion due to the curvature. Last, every time I've taken a hit to the face, I end up with a bruised or scraped chin from the bottom of the shield. At my recent black belt test, I ended up with two bloody gouges where the lower ventilation holes dug into my chin. I guess it's better than a black eye or broken nose, but I'm starting to look around for a better product that allows better visibility, doesn't fog up and causes less damage than my opponents!   

The face guard is a wonderful invention, however, there are no directions included with the headgear for attachment of the face guard. For something that serves to protect during sparring, directions would greatly increase the usefulness of such equipment.  

I really like the clear face shield idea, and wish there were more products on the market. I like the ventilation holes on this shield, but the optics leave much to be desired. There are visible wavy lines that distort vision through the shield. Also, it came with no instructions, and IMO was not a that good fit for the padded headgear. Rather overpriced for the quality.