It's not cheap but I bought the Brodit Proclip mainly because I wanted a dash mounted holder. It's a two piece holder, one part is a custom fit mounting plate for the dash and the second part is a holder for the device.
For the mouting plate there were 3 location options available for my car, a Ford Galaxy. I chose to mount above the air vents on the centre console.
For the iPhone there were 6 or more holders with combinations of fixed, tilt, passive, active and adjustable. As I keep my iPhone in a protective cover, which changes from month to month

, I bought the adjustable holder.
I also chose a passive holder as I wasn't sure at the time how I was going to charge or connect the iPhone and the holder was almost twice the cost (+£25) with a USB cable attached !!
A week later I upgraded the HU to a Sony MEX-BT3700 which has a USB port on the right which conveniently is just below the holder. And to complete it I imported a 7cm iStubz sync cable in black from Cablejive which is a perfect fit.
It may sound expensive but the Sony HU has BT which via the HFP mutes the music when I receive or make a call, also useful for Sat Nav. The phone also charges when connected to the USB port.
If you would like to see some pics or need more info just ask.