It does not fit perfectly on smaller faces (meaning it has a slight gap on the edges instead of being sealed) and I used it in construction and the visor fogged up the whole time. I couldn't see well. It fogs up from sweat and dust at the same time. It also impairs vision both below and slightly above. It's worth 3€ to 4€, not more.
It doesn't bother you when you wear it, and you can have it over your hat and forget that you still have it on your head. And it doesn't fall off when you run, etc. So it's good in that regard. (but when you leave it on your hat, it fogs up from sweat, especially in the summer)
It also does a relatively good job of protecting against particles and dust from entering the eyes, but not enough to prevent any dust from getting in. Dust always gets inside the mask because it doesn't have a seal.
It also has a somewhat soft fit, similar to snorkeling masks (but not as good of a fit), meaning it's not just hard plastic like some goggles.
UPDATE: Eventually, if you tighten the mask, it fits properly even on smaller faces, so there is no gap on the left/right sides. I also recommend removing the front sticker because it's clearly cleaner without it. The downside is that if you blow dust and have your eyes open, the dust still gets in.
UPDATE2: It actually has a gap at the nose, so no matter what you do, no matter what face you have... there will be a gap, and therefore if you blow dust and have your eyes open... it's very likely that the dust will get in your eyes. So these goggles are only for a different kind of use (e.g. for grinding).
UPDATE3: Overall, the mask is terrible... the main problem is that it fogs up every 20 seconds, and you have to take it off and blow air on it to defog it a bit, so you can see something.
UPDATE4: If you work in an open area and there is a lot of wind, then they don't fog up at all (meaning the weather plays a role), while if you work in a basement... they need cleaning every 10 seconds.
UPDATE5: Also, after a while of wearing it, it leaves marks on your face when you take it off.