Easily scratched and dented using finger nail. Cons: They are extremely brittle, break like an ice cube upon slight impact leaving perfect broken puzzle like jigs of debris.They are very floaty and easy to fly airframe due to its lightweight material. Usually a secondary choice for construction after EPO foam. Pros: They are extremely light, rigid and can be molded to any shape very popular for detailed scale models.Crash durability: 9/10 (Extremely tough).Pilot level requirement/suitability: Beginner-Intermediate.Most popular use in brand: TECHONE, Hobby King 3D profiles.Very bouncy material but hazardous when it get heavy in built. They also safe to fly and crashes into any object provided it was build with in less layer density. They are favor for being spongy, rubbery rigid and less hazardous during crashes and impact provided they were build in smaller size.
FPV/UAV use: EPP choice mostly popular on flying wing type platform such as Techone Pop wing and HK flying wing.Ideally for slow flyer in a form of flat sheet profile. The surface also have lots of micro pockets of holes that causes too much drag with the air. Cons: The bigger the models the heavier they get due to foam density.Usually popular for small to medium size profile 3D plane for indoor flights. Plane construction usually supported using embedded carbon spar/rods to maintain the shape of the wings and plane structure. High elastic and flexy property if slices in sheets. Pros: Dense sponge like foam material usually popular for making profile 3D plane "plank plane".Pilot level requirement/suitability: Beginners.Most popular use in brand: FMS, DURAFLY J-Power, Sky Angels, Hobby King gliders, Dynam.Due to their robust property sometimes ground object and living things may get damaged due to crash impact if the foam exceed their weight ratio. Most popular construction molding material to build glider type platform such as Sky Walker, HK Bixler, Zephyr lines and flying wings which spanned between 1.2~2.2m wingspan. FPV/UAV use: Usually these are number one choice for starter due to robust and tough material attributes.Cons: The bigger the models the heavier it get due to foam density per-size.Ideal material for beginners r/c pilot due to robust plane structure after crashes, easily glue back using hot glue if tore apart. Most prefered foam for molding detailed scale models. Resist dents and slight bumps due to elastic property. Pros: Very dense, rigid and elastic foam.Below are summary of Pros and Cons of various material used for Radio control/ FPV/UAV flight platform.