Opeth have been one of my favorite bands for a very long time. I absolutely love full-chord riffing, and Opeth put it to use better than any other band I've heard (most of them trying to imitate Opeth in some form).

I also absolutely love long songs. One of the things I enjoy is being able to get lost in what I'm listening to. Opeth are very good at creating music that I can get lost in, but still have enough going on to make me pay attention.

And for the record, I thought Watershed was amazing. It's definitely a hard album to listen to, but it feels rewarding to listen all the way through. Whereas most albums that are hard to listen to just suck.