12-03-2018 12:09 PM
12-04-2018 09:53 AM
I'm not sure what that is as I've never personally encountered it. From the information on this page, it looks like it might be an image of the drive before being converted from HFS+ to APFS so it could keep data safe & mobile during the conversion process, but I really don't know. They have instructions on converting it to a mountable DMG to access data within it.
See my suggestions in this post for alternate methods to set up your new SSD. Since you are using a version of OSX with APFS support, you could boot using Internet Recovery to perform the steps in paragraph two of my linked post.
12-04-2018 10:37 AM
I'm not sure SuperDuper creates the Recovery Partition, but I know Carbon Copy Cloner does. Otherwise both apps are good.
Thanks for the update.