Does anyone know if this liquid latex is high quality enough to be used in making casts?

I'd say don't try it.... we've tried using it a few times, it's low quality, extremely painful, strong smelling due to the high ammonia concentration and very lumpy. When you go to peel it off it breaks into several pieces and manages to stick no matter how carefully you prep with glycerin or lanolin products. you might be able to get it to work with an object but the number of tries to attempt it and potential damage to the object isn't worth it.