I have used a number of cast iron tubs and several fiberglass ones. The
fiberglass keeps the water warm a LOT longer.

On 6 May 2005 14:29:43 -0700, wrote:

Hmm.... I put cast iron tubs in my house (Kohler Villager, at $249
each), and the cost is about the same
as acrylic....
Advantages of cast:
--lasts almost forever (don't drop a hammer in one)
-- holds the heat a LOT longer (that is, if the person knows how do to
it right, that is put in the hottest water, and wait a few mins for
the iron to bring the temp down to a non scorching temp ;-)
-- no flexing
-- no scratching
-- quieter, in surrounding rooms

disadvantage:
-- heavy to install
-- needs a decent surround, like tile, though there are acrylic
surrounds