Was not an option when I bought mine. Mine has a threaded nut. It works great. I am sure for home use a threaded nut is fine.
The polishing compounds they offer are on the pricey side. I tried cheaper automotive polishes for plastic. They did not work as well. NOVUS polishes work well but the cost is about the same. I decided to stick with their polish. It works and I use so little it last a long time.