I first got a Bracketron friction mount... slides way too much. You have to drive real careful with it, and when you have over 400hp to the rear wheels, that's easier said then done.
Link to said mount: http://www.techforless.com/cgi-bin/t...GfHr&mv_pc=364
I purchased a dash mount (vent mount) from Best Buy. Easy to adjust and remove..