The Stone Care: Granite & Marble Cleaning Spray (1 QT) and Stone Care: Topical Granite & Marble Polish (1 QT) can be used on cultured marble effectively. These products will clean and add shine.
The Stone Care: ETCH REMOVER / Marble Polishing Powder is for use on real marble (travertine and limestone) only.
Do not use this product on cultured marble as it may damage the finish of cultured marble. Cultured marble is made with marble dust, but also a bunch of other chemicals and coatings. It is largely a plastic surface.
The Topical Stone Polish will add a bit of shine to your cultured marble and won't damage it at all.