Thanks for confirming. I did a Google search for Ester vs Mineral vs PAG and came across this link: Oil used In Automotive Air Conditioners

I guess I'll be using ester oil just to be compatible with either.

Another question, besides running an AC flush through the lines, is there anything I need to do with the compressor? Is there some sort of drain plug to dump out the old oil from or is just flushing/vacuuming the lines sufficient?