Sum 41 has had great success with many of their albums. I don't have a favorite album really. This is because no album sounds the same.
Their latest album which is Underclass Hero has a different sound to it with more twangy electric guitars and more of a raw indie sound. This album could have been better if genres were fused like their previous ones. For example, rap and rock are no longer present. But then again, it's part of their progression.
My favorite aspect of this album was that Sum 41 uses variety and has changed musical styles somewhat. Like Linkin Park, they have changed from rap-rock hip-hip oriented rock to more of an indie punk style.
This album features great acoustic ballads with tubular bells and violins also.
I don't know why this got such low ratings. It's Sum 41!