Fortunately, I was wrong with my assumption, because the mount holds bombproof. After 2 hours more or less "bumpier" ride it still held. Pull Even with really strong I could not them tearing the holder.
Only small criticism is that I have to squeeze very tight the bracket's smartphone because my phone (HTC One M8) is made of aluminum and therefore very easy to slip if you do not compress properly. So I can but live well. With my plastic protective cover that I have in 80% of cases on mobile keeps them even with light pressure bombproof. In addition, you can fold out small "feet".
From me there is a strong buy recommendation.