Turned my first Sierra/Manhattan pen today in a beautiful white acrylic. Sanded 400, 600, and 800. Then wet sanded with all grits of Micro Mesh. Finished by buffing/polishing with Novus fine scratch remover.
Looks real nice. White is definitely an underappreciated color. Last year I gave away over 50 pens in my unit for Christmas as part of my personal pens for troops campaign and the ones I did with white Corian were very popular. Especially on chrome, satin chrome and copper finishes.