if the other key is for the PATS bypass dont let them sell you the key with the buttons just use a standard pats key, if the new key has a start button then it might be worth it but i though the dealer ship only gave you another key fob with only one button, but i would stop by and talk to the guys at best buy for around $450-$500 you can get a much better RS system that has a real security system and a range of about a mile with a lifetime warranty.