Various Macintosh models have slightly different ROM codes. The Installer determines which model it is installing to, and installs the appropriate ROM patches for each model.
If you have already run the Installer on a volume and you want to transfer that System to another volume that will be used on the same or similar computer, it should be alright.
Also, if you do a customized install, and choose "System Software for any Macintosh", it should be alright using that volume on different Macintosh models.