OK, so let's discard all the possible negatives about this product. The description should say that this cooler is for laptops ranging in size from 15" and lower. I have a 15" computer and anything larger I would expect would be too close to the fans. A small space between laptop and fan is needed. Usually placing the "feet" of the computer does the trick, but larger coputers might end up having their "feet" too far out to place all four on the fan.
A second issue adressed by other review-ees is that the USB plug gets loose after use. I haven't used it long enough for that to occur, but I can imagine that if you try to use this fan on non-flat surfaces then it is possible for any USB-fitted cable to loose it's tightness.
It's extreamly quiet and I'm running it on the higher setting. This fan is so good that it has saved my computer! My built in computer fan died recently which meant that the heat would cause the computer to crash every 5 minutes. The cooler is compensating completely! This is impressive as I'm a student in the progress of writing my dissertation which means that my computer is switchen on for up to 14hours straight.
And finally let us not forget the dimensions, it only raises the computer about an inch = 2.5cm. And the design is stunning. It is also very light, so I doubt it would add much weight if you choose to travel with it.
To reiterate, as long as it is kept on a flat surface and used with a 15" or smaller laptop, it's a great investment.