because it is usally done in a singe cast there is really no bad casting (if from a good company). The detail is one thousand times better because of the casting process. Resin seems to form into tiny details better than Plastic which is injected into the mold. There are skunky resin kits too but that’s on the part of the person making the mold and rushing to put a product out. legend Production and various others are great companies to purchase resin sets. Also Resin companies make a variety of conversions for vehicles that a styrene company couldn’t make because of the changes in the expensive molds that would have to be done. Therefore Resin makes for a better variety of the same vehicle in different variant forms. IE the Sherman. You can buy a base model of a sherman and buy a resin conversion that isn’t available in plastic and turn that sherman into a bridge layer, or a rocket launcher or whatever. Resin is definately something you have to take great care in as it isn’t cheap to get replacement parts for… It’s really hard to explain but Resin is definately a great investment, and highly addictive!