Actually RetroMan, I would disagree with that
Technically, there is no difference, of course - otherwise something would be rather wrong with what we are doing!
But by installling from an original disk - you really have no guarantee that the disk is unmodified (virus, user hacking, hiscores, save games, corruption, etc.) and has no errors (bitrot, dirt, etc.). We see this *all the time* it is quite frightening how many original games submitted that we can't use.
But anyway, by installing from the CAPS images, you do have this guarantee!