I was really worried that this would be a junk product. I installed and tested it on an old crappy smartphone. At a speed of just over 80 km/h I didn't notice any movement at all. I took the bike home, grabbed my phone and did a few, shall we say, test rides. Then pulled onto the freeway and repeated my 80mph test. The iPhone was larger and still held in place well. I'm not suggesting that now, but I've put the bike to over 100 and still haven't budged. Since I usually ride slow and light, I'm sure my bike really talked about it. But I have faith in the product. They even came with extra brackets so I would say they got dodgy, you can change them. Well designed and perfect for me.