Hi rollyfoster
I agree with some of the comments/responses here, but as you are probably aware Aperture can store your files in different locations - depending if you had a referenced library or not.
It's always good practice to back up your files, so I would recommend using the export features in Aperture and export the photos to a 'new' area - internal or external hard disc or somewhere else depending on how much disc space they use up. This means you would always have a copy tucked away and 'unlinked to any other application.
You could then import to Photos from Aperture - (when you YOU feel it's ready or acceptable for use). You can probably tell here that I'm not a fan of it in its current state and probably shouldn't have been released yet.
Regards, Number 7