The best advantages of acrylic is they are deeper. Acrylic tubs are lighter, stronger and easier to install than cast iron tubs. Even though acrylic can begin to look dull, there are way more pros than cons to having an acrylic tub.
Cast iron is expected in more expensive homes. In less expensive homes, cast iron may be appreciated but acrylic would be acceptable.A cast iron tub requires more floor support, more labor to install and is more expensive to transport.
Also, the natural warmth and thickness of acrylic tubs combine to preserve heat much longer than a cast iron tub. Cast iron tubs draw all the heat out of the water to become warm, only then will it radiate heat ( essentially once the tub is warm you would have to drain it quickly and refill to have a hot tub with hot water). These days, acrylic tubs are being made of many different layers, allowing them to hold heat for longer periods of time. The only real benefit of a cast iron tub is that its overall look will last. Additionally Acrylic is repairable.
Care and Cleaning: Never run pure hot water at the beginning of filling it will cause crazing (a cracking effect of the top layer and use a grease cutting soap to clean). No scratching on acrylic or cast iron people!

APPOLLO, these posts your commenting on are years old.

Ah, but still relevant.