I am overall very happy with my F90BT and have had it about a month. Ipod controls work great, voice control works pretty good if you speak slow and clearly, and the bluetooth works great for me with a nextel i870 phone. I have installed a bunch of hacks/mods that improved it a lot though.
I had one problem sofar where the navigation stopped working after watching a movie while driving. I had to pull over and turn the car off and on to reset it. Why is there no power off button on the unit?