Vent mounts are usually pretty weak. A Windshield mount, constantly exposed to the sun, will dry out and be useless in a couple of years (even the ones with the levers). Try Mountek nGroove Universal CD Slot Mount. They have a few different styles, and they all mount in the CD slot of the car radio (which is pretty useless if you have a phone with a decent amount of storage). Mine have been working well for years. (They're big - my Note 3 is nowhere near the limit. Even a Magellan GPS fits with no problem.)
I recently started using the Steelie Car Mount. There are some draw back, you have to attach a magnet to the back of your phone and a steel bearing to your dash. I like it so far.