3-4 times cheaper than a GoPro premium for the same functions (only real difference, the absence of a real mode> 30 frames per second, but frankly at this price is largely forgive him, the slow motions will be a little less pretty), picture quality and sound similar, and comes with plenty of standard accessories (unlike its competitor)!
In short, a must for sports enthusiasts, adventurers, or just technology fans. Personally, I love to use it when I travel on the road (to film roadtrips), and I think soon test its use on a boat and roller coasters in amusement parks.
There are many copies of more or less quality of this product, it is important to check that the product is authentic (see the internet to find the guides that explain how to choose). This model (in my case that sold by Chance & Future) is authentic (and most recent), I have had no worries.