In HoA page 40 Elend outpushes a steel inquisitor, who a few pages later is revealed to only have a single f-steel spike extra, so he has 2-3 times regular steel power, depending on if he was a natural coinshot or not.
So Lerasium beads the size of the one Elend ate make you at least 3-4 time more powerful than ordinary allomancers