HiC,
If you go to the Garmin website, you can download a "training simulator" version of some of their GPS systems. I've got the 430 simulator on my home PC - very useful for learning how to use the GPS without having to worry about actually flying the aircraft at the same time.
The simulators also come with 2 databases, and you can swap between databases with a couple of mouse-clicks.
I tried flying around the UK on the American database a while ago. Most of the information is there, but cut down - all the airfields are there, for example, but the runway layout of UK airfields isn't shown on the American database.
I don't know how accurately the databases in the simulation match the real-life databases - I've found a few differences, but they might just be different revisions of the databases. But if the simulation databases are accurate, then yes, I think it would be perfectly possible to follow a flight anywhere in the world, whichever database you've got installed.
FFF
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