We ate at the Backlot Express in October and our food was good. Typical Burgers and Chicken Strips, but tasty. Deserts were really good.
We have eaten at the Commissary on past trips and we will not eat there again, It was really bad.
All in all, I think MGM has the worsst CS food of all of the parks. When we ate at Backlot Express, I was not expecting much, and we were pleasantly surprised.