I'm looking to find a heavy guage 4 string set, and would like some recommendations. I'm going to be playing in a metal band with my brother, and for this particular band he tunes down to about C#. Right now I'm using .045-.105s, and I'd like to try something heavier to try and get a little tension back. I'd like some recommendations of heavy strings, and maybe a comment on the tone of each. I'm not picky, but I'd like to have an idea of what to expect as I try out a few brands. Thanks a heap in advance.  my preference is nickel plated round wounds, but I'm not totally agains steels. I might consider trying a flatwound, but I'm not sure I'll find one with a tone that fits the music.