I self taught myself guitar and started off trying to play COB. I played trumpet and keyboard before that so it wasn't terrible, but it took a while to actually get from beginning to end of a song. COB can be fine to learn from, as long as you do it right. Play slow and try to play things right, and if you do that playing COB stuff you'll become quite good actually. Practice some melodies you look like slowly with a metronome.
That said, I think rhythm for Sixpounder is easy for a beginner, as is bed of razors. As long as you can do some fast picking Northpole is easy, too. The rest of the songs have easy and hard parts mixed, like hate me, everytime I die, etc...