Years ago I tried so many and wasted my money.  One day I realized all the work cars had mounting systems from one company.  I've not bought a mount for anything except from them since.  
Ram Mount.
I have several.  All of which are still in use as much as 10 years on and then some.  Don't let the old suction cup thing fool you.  I can mount mine to my winshield and shake the entire vehicle without it coming loose.