I was impressed by how comfortable these goggles are and I found that they provided a very good seal around my face so didn't leak whilst using them. The goggles also stayed secure and the straps did not loosen whilst using them. I was however extremely disappointed by how much they fogged up after only a few minutes use, which is why I have rated the googles only 2 stars.
The Amazon description claims the goggles offer 'incredible moisture control using Fogbuster technology, guaranteeing consistent clarity of vision combined' -- certainly not in my experience! I could hardly swim 50 metres before having to remove the goggles to clear out the moisture that had built up on the lens, it was like swimming with severe cataracts. It became so foggy whilst swimming that I would actually consider it dangerous and wearing the goggles seriously hindered the enjoyment of my swim.
I purchased these goggles to replace a lost pair of Aqua Sphere Kayenne Goggles
, I'm going to return these and buy another set of Aqua Spheres instead as they are superior in my opinion.