Can I use the same memory card between different models or versions of the dataPAC?
Not exactly. You can use the same card with a dataPAC 1250 and a dataPAC 1500 or with version 3 and version 4 for example. But the card will have to be re-initialized whenever you change dataPAC models or versions. And re-initializing includes re-formatting so all the data on your card will be deleted.