Disclaimer - I have never seen this line, so working from their webpage pictures and descriptions only.
If you have snow in the winter, I would stay far away from these - the lower profile the vent, the more likely you will form icing right below it from the exhaust melting the snow, and the more likely an ice dam will form there and back water up into the vent. In addition, in snow conditions the airflow will be largely blocked by a very few inches of snow, and snow melting on the surface of it will run right down into the vent and can freeze there, causing leakage into the attic or duct - just what you do NOT want.
For non-snow areas, I would be very leery also - such a flat design HAS to have significantly more flow resistance than a wide-open traditional vent. Personally, I do not give a darn for the appearance of the vent - it is a roof for goodness sake, not a work of art, and I do not spend hours in a deck chair looking at it - in fact, most people do not even see serious damage on their own roof - their neighbors are the ones who tell them because they see it from THEIR house. I want vents that work well and do not cause icing, not something designed to blend into the roof.
