The clamps hold on to the vent great and do not shake even on rocky/gravel roads

Holds my phone [Huawei Honor 6x] securely, even over bumpy roads

Drove for 9 days on horrible roads, including off-roading and the mount never came off the dash and it never dropped my phone

Does not slip on bumpy roads even though my vents are vertical & was worried the grip would not hold well, but it's fine.

Very easy to install and allows me to use my phone hands free as well as to see my phone's GPS

Also, I didn't consider that when placing an air vent mount holder the weight of the phone will cause the vent to drop down, as well as become useless if you have small vents.