Hello...

If you have a 530 or 430, does it accept the same updates? Or are the
updates specific to each machine. Also, if you have both in your
plane (one of each), do you have to purchase 2 updates?

I notice that some 530s come with 'terrain'... is this an option from
garmin? Can it be added later or do you have to upgrade the whole
unit?

Lastly, when waas becomes available... is it a simple software upgrade?
and any word on the charge of this upgrade?

Thanks,

-dr