Not very clear vision
I assume they protect as advertised (not having suffered an accident to test them.) However, I stopped wearing them while I was sanding because I was having so much trouble seeing through the lens. Reasonably comfortable...

I can still see- sort of
The goggles have worked great so far- they fit around my fat head pretty good and I have only had a minimal problem with fogging. The only thing I don't really care for is that the lens seems to scratch up pretty easily- now I have a spot on one side that I keep looking at out of reflex. Considering all of the debris it has kept out of my eyes it is a small price to pay.

Huge enough for me
Nothing can fit all people. My hat size is 7-3/4 or XL and these goggles fit great. However, I wouldn't guarantee that they will provide adequate clearance for large frame eye glasses.

Way too big
I bought these goggles for my Chem lab but was disappointed when I first put them on; these goggles are huge! They not only cover my eyes, but also my nose, cheeks, and forehead. It feels more like that I'm wearing a mask rather than a pair of goggles.

These goggles fog up (I know description says otherwise) but I have to periodically take it off to get rid of the water mist that blinds me.

I have a 4 hour lab class and by the end of it, the goggles have drilled lines into my cheeks/forhead where it was resting. These marks last for hours.

Conclusion, unless you have HUGE prescription glass and can't find goggles to fit over, don't bother. Get something smaller and more comfortable.

Decent impact goggles
These googles are well made, and decently priced. I purcheded them because I cannot wear the standard safety glasses over my perscription eyewear. The goggles themselves are fairly large; more then big enough to fit over pretty much any pair of glasses you may be wearing.

If anything, they may be slightly too big, but their largeness gives you a fairly unobstructed field of vision while wearing. The portion that rests against your face is made of a soft rubber-like plastic and they are fairly comfortable to wear.