[TheChampJT]

I haven't personally done this yet, but I do use Spb Backup, and have done a restore. During the restore, it asks if you have a different ROM version, and asks if it's the same device. There are other options in the ROM restore feature, such as restoring all data, and overwriting ROM files. So you should be safe from the looks of it, I even think restoring to a new ROM was one of there biggest added features.