For my main rig I have a Yaesu FT-8800R. Since I don't want it in the car all the time I mount the main unit on the back of the center console/arm-rest, zip-tie the remote-head to the hand-brake, and plug the audio into my car stereo. I also have a Yaesu VX-127 that I cross-band with the 8800 so that I can get out of the car and still be in contact. As a chief of controls and a stage captain I find this extremely invaluable. In fact, the mobility of the HT combined with the power of the mobile rig became a real necessity when all at once I had to do FTC timing, radio, and traffic control at Black River Stages last year.
Matt