Using the words "good" and "plastic" in the same sentence is usually an oxymoron. But there are so many "plastic" tub manufacturers that we would have to know which ones are available in your area.
Yeah--I know there aren't many great acrylic tubs out there--I don't know if they have room for the Mariposa. Hmm. Maybe the Toto, if we can find it. Isn't the Dynametric built with a raised bottom?