I don't have anything negative to say about The Muppet Movie. It's one of the earliest films I saw as a child, it's the first Muppet film I saw, and I've loved it ever since. The Never Before sequence I think is a little slow and while Frank's/Piggy's singing is rough, I think it's meant to be part of the gag at how bad it is. But I'm willing to overlook that small little lull in the film in an otherwise perfect movie.