The Mystic is the particle pearl in the mid-priced line, so it's pretty much the replacement for the RS-P. According to the website, the Mystic comes 2000-grit polished. If you're looking for something to handle heavier oil, you could take it down to 800-grit dull or lower. That'll handle plenty of oil.
It looks like the new Epic Quest is a dull solid particle for oil. There's the popular Epic Battle as the usual oiler. It looks like the Quest is replacing the Battle (both being solid particles), though I have no idea when the Quest is coming out.
SH