I haven't tried Polywatch on anything other than watches, but: If you are afraid it'll smear it or be too rough then you might consider trying out toothpaste instead. Toothpaste works somewhat like a light version of Polywatch. I usually use instead of Polywatch if an acrylic has light scratches.
It's hard to tell how good a result you'll get without knowing the exact finish of the material.
Good luck :)
Cheers,
Mabuse