If it is simply price per pound, polyester is commonly the lower cost; if you are looking at value for your money, then Aqua-Resin is considerably less costly.
Because Aqua-Resin (AR) is so much easier to work with than polyester, generally the labor savings alone offset any difference in pricing. Since labor costs can be 10 to 20 times the cost of the materials, a savings of just 10% in labor can make AR less costly than polyester.
Add to that savings in respirators and protective clothing, exhaust equipment/mechanical ventilation, solvents, water cleanup, hazmat shipping and disposal, and EPA and OSHA Compliance issues—not to mention AR’s very long shelf life. In addition you have fire regulations and insurance, extra liability, worker moral and sick days.
One of the most costly of all issues with polyester seems to be worker attrition; polyester workers are often concerned about their health and decide to move. Retraining a new worker is very costly both in training and downtime. Styrene has been declared “reasonably anticipated” to cause cancer by OSHA.
Now that we are in the middle of the “Green Revolution”, there is quite a bit of value added in using a green/sustainable product such as AR. AR is only 10% petrochemical derived as opposed to polyester which is 100% petrochemical. Many companies feel their bottom line is increased by advertising the materials they work with are even slightly more green and sustainably produced than they were before. AR is in fact 90% free of petrochemicals, so if customer perception and benefiting the ecology is of value to your company you might want to add this to your considerations for your bottom line.
Ironman photos from http://www.xrobots.co.uk/ironmancostume/