Several good points about using an iron block for a real street car.

Here is one more thing to consider. An iron Hemi block and iron Hemi heads will make the car so front heavy, it will handle worse than it does now.
I do love my '73 Cuda with an iron 440 wedge. But it does handle like crap, IMO. The added weight of Hemi parts ???

Pros and Cons.
The new World (Bill Mitchell Products) aluminum blocks have o-rings around the sleeves.