When we installed our Toto cast iron tubs (1525's), DH "wrapped" as much insulation around them as he could, while the walls behind/around them were still open. Someone here mentioned doing that. We are very, very happy with our tubs, BTW. If we ever move/have to re-do bathrooms, we'd use Toto cast iron tubs again (maybe longer ones if space allows).

Why Sanitary napkins as shown in the photo? Also lotion? Are you going to do a hot water hook up to the tub? I know people who have had hot water hook up outside so they can rinse and wash the dogs before they come in the house. I always bring my boy in and use the warm water and sprayer in the tub. He jumps in and out by himself, does not slip on the non -slip bottom, but one of those rubber mats would work.

I used a Kohler Expanse tub, in one of our bathrooms. They are acrylic. When installing the tub, set it in mortar (under the tub). This gives a very solid feel.

We had an old cast iron with bad rusting on the overflow drain. instead of replacing it we had Miracle Method refinish it. They repaired the rusted out spot and replaced drains. Our tile was in good space but an ugly yellow so I had them spray the tub surround too. So much easier than retiling, and it looks great. It does stink for a few days but worth it.