Absoloutly gonna agree with Flah here and say Children of Bodom's cover of Shot in the Dark was horrible. Fear Factory's cover of Cars wasn't a bad cover in the same way, it was just too like the original.
I really don't like Matt's vocals when he's not being agressive (i.e. the end of Pillars of Serpents, most of If I Could Collapse the Masses). This could be a pretty decent metalcore band if he would just stick to screaming.