well forged would allways be my frist choice, i used many cast eagle cranks for circle track drag and street
the key in my mind is having it balanced correctly ,eagle cranks unlike some other china cranks normally come with rough balance weight of 1900 for a small block old stock gm cranks are about 1950
so if you are going to exceed 4500 , as far as i am concerned it must be balanced to match your piston /rod combo
someone will say i bought a balanced crank then tell me you are using piston rods the got other places , if they were not all in the same place at one time they probably are not balanced the just think because it has a bobweight
and many times some one will bring a failed engine and i will find external flywheels on internal balanced ,this is a problem you run into on building 383 and 400 ,454
it will be the best 200-300 you spent