Havent heard Opposite of December but im willing to check it out for sure.
But just to be clear, I didnt mean to imply that I disliked scream (and/or metal) vocals, I listen to a good amount of hard metal, hardcore punk, and other music that has illegible vocals. I just meant, in this case of PTH, Im glad the vocals are how they are because I feel it goes with the music very well. If he was screaming his head off I wouldnt see as much appeal in the group with the exception of the obvious instrument skill. The erraticness of their songs instrumentally is what really got me into them. It's just so off-timed and purposely eccentric, that it takes a long time to get one song in your head into full memory. I love shit like that.
I'll check out Poison the Well though since you mentioned them, havent heard 'em.