Firstly, it's a very stylish and well thought out product. Looks nice, comes in a very big box for what it is, but the supplied microUSB-lighter port cable is nice and long (about 1.5m), so you should be able to mount it where you want it. It's got the usual suction cup mounting which is easy to get to stick to the windscreen and other such very smooth surfaces. You'll need to buy yourself a separate 3.5mm audio cable to pipe audio into your car stereo (assuming you're not Bluetoothing).
Getting the phone into the dock can be tricky - it is a very snug fit as everyone notes, and there is a knack for popping it out by pressing through in a corner of the cut-out for the camera - even if you still have to use a fair amount of force.
My main niggle is that the car mode in the Galaxy Nexus doesn't pipe the audio from a phone call through the line out of the car dock (I am on Jelly Bean OS) but from reading the forums this seems to be a bug in the software, not the dock as the music audio is fine. Am hoping for a fix to that soon!