Dreadnaut's advice comes from experience. My advice matches his. Buy mold release products that are made to resist the chemical penetration of epoxy solvents, or fiberglass resin solvents. Your final results will be better over a very long time, with a seasoned mold, that has repeated coats of proper release agents. A single can of Partall will last a long time. It's a small expense to get the best results.
When doing layup of large 10 foot wide by 20 foot long flat sheets, on slick, glossy, formica topped laminate tables....you can get away with just a good coat of carnuba wax....even plain old Johnson's furniture wax. When you get into molds with multiple curves, tight halfrounds, long slender sections....the best release agents get you two things.
1. You get a clean shiny part, out of the mold. 2. Your mold is ready to go again with a quick coat and buff.
Have fun, John