Lens help please! i either want the sigma 50mm f2.8 or the 105mm f2.8(both macro) don't know which to get!?

i need a good macro lens.. ive done alot of reasearch on these 2, (narrowed it down to 2 lenses) and i cant decide weither the 50mm or the 105mm are better for me.. im thinking the 105mm but i dont know if it is heavy or cluncky or what.. and i dont know if the 50mm is 2 short of a focal leingth.. heelpp! (if you could add sample images that would be great) oh and i am also leaning towards teh 50mm because it is cheaper.