Key fob...
i have both keys & the chrome one stays in my bedroom drawer as a backup. i might as well use the already worn key not that it matters because it doesn't leave my pocket anyway thanks to keyless go! which is the best key imo.
unless I lose a key fob or 1 stops working and im forced to replace, u will catch me dead before u catch me spending $300+ for a new fob because my perfectly fine keyfob is dated or worn
..what a waste, i'd rather put that money towards mods. or tires. anything besides a key 

