I think it would do well but not better than Beyonce's.
It would probably open up with 150,000 and have a slow and steady life span like most of all her other albums.
The key would be for Rihanna to continue her musical break and when it comes time to release a new album, have a strategic and organized plan for the singles. And let them breathe for a while. Her last two eras were so messy with the single releases/music video releases... Having unfinished songs on the albums
I think all those things played a small part in her album sales. They could've been better. Like someone else said, Rihanna needs to make her album releases more of an "event." Which she could easily do but for whatever reason, her album cycles are messy as hell.