I have had this mask for about two years. I love it though I wish that it had a standard sized mask strap. I already am having difficulting in finding a spare to put in my safety kit.
While I was initially concerned about what looks like a barely adequate attachment for the strap adjustment buckle to the mask, it is still going like new there as well. I guess this part just does not look as substantial as some other brands.
I will agree that these masks tend to fog more than any other mask I have ever had. I have cleaned them with toothpaste (it is what I use for my defog anyway) many times. It does finally seem to be getting somewhat better after 100-150 dives.
The mask is the most comfortable I have ever used, and it allows the greatest field of vision I have ever seen in balance with low volume. I have never had a problem with it sealing on my face whether with or without a hood. I have never had any leaking issues at all.
In the end, like everything else about dive equipment, each thing has its pluses and minuses. I still think the pluses come out ahead with the Mares X-Vision.