The Mudder silicone cell phone mat does exactly what it is intended to do. I have used the product on smooth roads as well as bumpy roads and the phone and mat stay in place. In the video I am traveling down the interstate at 72 mph and you will see where I hit a rough spot on a bridge and the phone and mat stayed in place. This works great for holding your phone if you are using it for a gps. The only downfall I see with the mat is when you slide the holders, they tend to pop out of the slot very easily and you have to monkey around with it to get them back in. The Mudder silicone cell phone mat was sent to me free of charge or at a discounted price in exchange for my honest and unbiased review based on my experience with the product.