i had a steel 440 crank and '73 cast 440 crank.. put them both on the bathroom scales and they weighed the same. i know it's not precise weighing but it was what it was .i wouldn't be afraid of a cast crank at a reasonable power level. reasonable is maybe 500hp to me.
I've weighed both as well. 73 lbs. as I recall regardless of whether they are cast or forged.
I weighed a 383 steel, 400 cast, 440 steel and 440 cast, all 4 were 76 lbs.
.i wouldn't be afraid of a cast crank at a reasonable power level. reasonable is maybe 500hp to me. 
