I rented a mustang when my SVX got totaled. Of course, this was a basic model, and not a GT, etc. But it did have an "8".
The power was reasonable, but the interior looked extremely plastic and cheap. I wasn't impressed at all. The stereo had about the same sound quality as they did back in the 70's. And it wasn't that great then.
The interior gives the Mustang a resounding 2 on a 10 scale. It's horrible.