hi guys, i have a 2.0 honda accord coupe SE. w reg(2000). i believe this bekcer unit came as standard in the car. i was wondering if:

1 - this unit is going to be any good as a satnav
2 - can i hook up an mp3 player (ipod) to this unit and how (as it already has a sub out.
3 - if i cant connect an mp3 player to it, can i hook up a cd changer to it?
4 - if i remove the unit to put a more modern headunit in there, does the gps built into the car have any other functions?

Thanks for the help in advance guys!