inputs.text: good not great larger units - purchased use tomtom xxl 540 series gps base weighted perfectly didnt move even though cars dash little flat surface hold base steady arms grip unit bit short secure large unit like xxl place grip xxl side arms fully extended arent tight would like bottom arms arent quite long enough keep xxl snug either difficult wedge xxl right play every time use mount annoying eventually though able wedge xxl mount way keeps secure unless im driving rough conditions brake suddenly not problem smaller gps units tried tomtom one worked beautifully summarize isnt best choice gps larger average like tomtom xxl works well small averagesized units