The midfield pair arrived in the final weeks of the summer market.
"I was delighted to sign those players and what that gives us now that we didn't have before is options," the United boss said.
"What we have to have this season is a good enough squad to serve us in every game we play and Hatem Ben Arfa and Cheick give us something different.
"Hatem is a flair player and he is a little bit different to what we've got and that gives us options."
He added: "Our squad is definitely stronger. It isn't just about what we've got today or the next day, it is about coping when we're stretched with injuries and hopefully we are better equipped to do that now."