Americast vs. acrylic

I gutted a bathroom and chucked the claw foot tub. Starting the rough in for the house on Monday, and my plumber and I were discussing what kind of tub to put in. Given that we don't really want to wrestle a cast iron tub up a narrow flight of stairs, and our various biases, that narrowed down the choice to acrylic or americast pretty much.

Is there any consensus about which is more durable? I searched americast on this site, and responses seemed all over the place.

Oh, I managed to talk him out of having the tub on site for the rough in by promising to leave the ceiling open under the bathroom, so there's a bit of time

Kinda answered your own question there - everyone has an opinion. We've installed a number of each and i will tell you not all acrylic/fiberglass are created equal. Search here for some threads on quality units - there was a recent one.

Both are durable, and can last decades if installed and taken care of properly.

Yeah, I was hoping I missed something. Is it fair to say acrylic gets dull, and americast chips? It's going in a rental if that matters.

Not sure what you mean by installed incorrectly? Installing a tub seems pretty straight forward to me... ? Leaving out the usual (and creative.. ) DIY mistakes.

Though I might do something different than a few things I've seen here - specifically, I bed the tub in modified thin set mixed stiff, not regular mortar. Haven't had an issue so far, anyone think it's bad practice?

I've seen a bunch of 100 year old cast iron tubs in great shape... But ugh.

Oh and given sterling is Kohler, the tubs should be as good?