How do I update my Honda Accord Navigation System?

[Jeff M]

A friend of mine said he could get me an .iso file of the newest honda navigation dvd and all I would have to do is burn it to a double-layer DVD and put it in my navigation system and it would work. He is wanting to charge me like $20 which is way cheaper than the $199.99 honda charges so I was just wondering. Will that work or do the disks have some kind of securty code/system on them that would make this not work? Any answers are really appreciated so I don't waste my $20 bucks