Well, awhile back I went through a really big death metal/growling vocals stage in my music listening, and when I got out of that, I actually found it hard to listen to regular clean vocals again. I eventually got through it though. Maybe you just need some more time to let the music settle in your mind? I\'ve always admired Mikael for his incredible vocal range. In fact, good growling vocals are actually really hard to do, just like good clean vocals, unless of course if you\'re a natural. Clean vocals just can\'t properly portray the angry and dark emotions in many of opeth\'s songs. But on songs like Face of Melinda, which are sad and tragic, they fit perfectly. Just my take.
Oh, and to answer your question, most Opeth songs feature the growling vocals with occasional clean vocal breaks dispersed throughout. Off the top of my head, I think there is only one other song of their\'s that has only clean vocals. Track 3 off of Blackwater Park (I forget the bloody name of it).
