Love, love, love the mountek smart phone holder! Comes w/ 2 magnets - smaller & larger sizes.
The larger one holds my iPhone 6+ perfectly! The smaller magnet works perfectly w/ my son's iPhone 5, when he borrows the car.
Excellent for using the map app to navigate - which I do almost daily. Love that it's White -so when It's removed to use the radio (Honda CRV) it's easily found in my black purse.
Whether or not it blocks anything in your vehicle will depend on your particular dashboard design. Some cars have the CD slot above the radio; some are below the radio.
If I had a smaller model iPhone it probably wouldn't interfere w/ the radio.
This holder ONLY works when anchored into a CD player opening. It doesn't go in all the way, just enough to secure itself to hold the weight of the phone.
The only way this could be improved, is if it had the option to be installed upside down, to allow more access to the dash board below.
Easily installed & secured. I don't like the air vent devices, however I suppose it keeps the device cooler in the summer, w/ the a/c blowing on it.