I started with a Sanyo 4500 then went to a Sanyo 4900 then to a Treo 300 then upgraded to the 600. Long gone was the 4500. I just sold my 300 but still have the 4900. Should I sell the 4900 or keep it as a emergency spare phone in case the 600 breaks, gets lost or stolen to hold me over till a replacement 600 arrives? That's the only instances I can think of needing a spare. What do you think? What would you do?