Hi Silent,
Yes, the release candidate of dCore is stable and safe, is made of the same Debian files as the stable one but with the scripting routines of importsce updated to allow more features. In fact, the most current one usually has bugfixes for errors that may exist in the previous releases.
If you import a file list with the "importsce -f file" command, it is made into one sce that can be transported where you wish and downloaded and used on any dCore system, provided you did not use the -d option for deps. In that case, just also copy the depdendent sce's. You can add different Debian repos to your package system also, search the forum for the specifics.