This should be a decent test for Benn who is making good progress as a prospect in the welterweight division. Chris Algieri is a former world champion but is at the end of the his career. He should still have enough left to test Benn especially early on. Benn has improved massively throughout his career but is still a prospect who is vulnerable to being upset due to his inexperience and aggressive style.
I don’t think Chris Algieri will be the one to upset him as he’s at the end of his career and doesn’t have the power to stop Benn in his tracks. After a few close early rounds I think Algieri will get caught with something big and overwhelmed when Benn follows up. The referee will likely step in with Algieri taking punishment on the ropes.