totally a matter of opinion. but in my expierience, i get tones that my ears like more with thinner bass strings. as marcus said, it gives muh tone more bite and a snarl that cannot be had with telephone wire. though thicker strings do sound fatter, they also tend to sound less defined. again, my opinion, and know some of y'all and dozen other people that disagree, but tone is always a matter of personal taste (yea yea, i know it will be suggested that i have bad taste...)
I'll post some clips later when i get home from the doctor. i gets muh cast off and in the clear, and hopefully get to play guitar again, yay!