Not sure what the line rating is per say, but, according to Ben's website the weight rating on it is 3oz - 7oz. I would contact Ben for more specifics on his rod. He would be able to enlighten you better than any of us could.
That pike has some girth to it!
I'm sure in the secluded parts of Canada somewhere there is a 100Lb muskie swimming around. That would not surprise me one bit. I also think not too long ago the WR tiger muskie was caught (in MN if I remember correctly). It could have just been a state record, but that tiger was an absolute monster!