Hi, I just received a CNSD-250FM as a gift and I'm really not sure I need this. I havn't really been looking into upgrades and such for some time as I've been content with my 3.02 firmware and mods etc. So, I'm trying to find out if its worth me keeping this and was wondering if anyone knows if it has an upgraded firmware or just new maps? It does say 'upgrade navigation features' on the cover. Thanks!

the 250fm is for the f500bt, whereas the 200fm is the same update for all the other higher models.

Check this out : http://ds1.downloadtech.net/cn1010/firmware/AVIC/CNSD-200FM.pdf