I'd prefer not to add a demo category for that or even individual systems at this time. The only split sub-cat names we have now are in the SMS category and those are set to be looked into in the future.
If there is a good amount of actual demos that are found for either or both systems, we can consider it. For now, we do not need to make a sub-cat just for those as the release type option on the entry already allows for setting the item as a demo.