Molds will not last as long as they would if Pol-Ease 2300 Release Agent was used. The main reason for using Pol-Ease 2500 in a polyurethane mold would be to cast a part that can be cleaned more easily than a part covered with Pol-Ease 2300. This is beneficial when painting cast parts. After spraying, brush out this release agent with a soft brush to help improve results. No drying time necessary.